Finding Oxidation Numbers Practice Problems and Answers Wayne Breslyn (Dr. B.) 2026-09-21 | Finding Oxidation Numbers Practice Problems and Answers
Predicting Chemical Reactions: Getting Started Wayne Breslyn (Dr. B.) 2024-10-06 | Full course playlist: youtube.com/playlist?list=PLZR1BGWBaZ1xDIShNcoCqdRkheRyyAyDRDownload the Course Guide!breslyn.org/uploads/Workbook-Predicting.pdfCourse Videos🎞️Getting Started🎞️Single, Double, and Combustion Rxns:🎞️Decomposition Rxns:🎞️Combination Rxns:🎞️Are you ready for your exam or quiz? Other Resources:🔹My other courses: youtube.com/@wbreslyn/courses🔹My website: https://www.Breslyn.org🔹Types of Reactions: youtu.be/ddY2RQ3ziLo🔹Finding Ionic Charge: youtu.be/M22YQ1hHhEY🔹Memorizing Polyatomic Ions: youtu.be/vepxhM_bZqk🔹Identifying Metals and Non-Metals: youtu.be/OoooStZQHdAJoin this channel to get full access to Dr. B's chemistry guides:youtube.com/channel/UCaUF73YX-uQTGwDB20I3n3g/join
Can isotopes also be ions? Wayne Breslyn (Dr. B.) 2024-10-04 | In this video, we explore whether isotopes can also be ions. Starting with chlorine as an example, we know that chlorine always has 17 protons because that defines the element. However, the number of neutrons can vary. For instance, chlorine can have 18 neutrons, making it chlorine-35, or 20 neutrons, making it chlorine-37. These are both isotopes of chlorine, as they have the same number of protons but different numbers of neutrons.In terms of ions, both isotopes can gain one electron to complete their octet when they bond with another element, like sodium. Sodium would lose one electron, and when chlorine gains that electron, it becomes negatively charged because electrons are negatively charged. The sodium atom would be a positive ion, Na+. So, both chlorine-35 and chlorine-37 can become negative ions (Cl⁻). In this case, you'd have chloride-35 as a negative ion and chloride-37 as a negative ion. Therefore, isotopes can indeed also be ions!Chlorine Bohr Diagram Image:upload.wikimedia.org/wikipedia/commons/1/1d/17_chlorine_%28Cl%29_Bohr_model.pngAhazard.sciencewriter, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
Average Atomic Mass vs. Mass Number Wayne Breslyn (Dr. B.) 2024-09-29 | When we compare the average atomic mass and the mass number, it's important to understand what each term represents. Let's use chlorine as an example. Chlorine exists mainly as two isotopes: chlorine-35 and chlorine-37. The mass number of an atom is simply the sum of its protons and neutrons. For chlorine-35, this means 17 protons plus 18 neutrons, giving us a mass number of 35. For chlorine-37, the 17 protons plus 20 neutrons give us a mass number of 37. These mass numbers are always whole numbers because they count the actual particles in the atom.App used in video: https://phet.colorado.edu/en/simulations/isotopes-and-atomic-massHowever, when you look at the periodic table, the atomic mass of chlorine is not a whole number—it's about 35.45. This value is the average atomic mass, which accounts for the different isotopes of chlorine and their relative abundances. In a sample of chlorine, you'll have a mix of chlorine-35 and chlorine-37 atoms. The average atomic mass is calculated by taking into account how much of each isotope is present in nature and averaging their masses. Because this is an average, and because isotopes don't occur in equal amounts, the average atomic mass ends up being a decimal.So, while the mass number is specific to an individual atom and is a whole number, the average atomic mass reflects the weighted average of all the isotopes of an element found in nature, which is why it's typically a decimal. This distinction helps us understand both the specific characteristics of individual atoms and the overall nature of an element as it appears in the world.
Supercut: How to Draw Lewis Structures for Chemistry – Basics, Formal Charge, & Resonance Wayne Breslyn (Dr. B.) 2024-09-23 | This supercut is your guide to mastering Lewis structures step-by-step. It covers basic concepts to advanced topics like formal charge and resonance. Whether you're a high school or college student, or just brushing up on chemistry, you'll find everything you need to confidently draw Lewis structures for both molecules and ionic compounds.By the end of this video, you’ll be able to:Draw Lewis structures step-by-step for any molecule or compoundCalculate formal charge and practice it with problemsUnderstand resonance and how it applies to chemistryWork through examples of Lewis structures for ionic compoundsThis video starts out easy and gets progressively more challenging, making it perfect for anyone looking to strengthen their chemistry skills at any level.For more help on chemistry, visit my website:www.breslyn.org #LewisStructures #ChemistryTutorial #FormalCharge #Resonance #IonicCompounds #ChemistryHelp
How to Use AXE Notation to Find Molecular Geometry (Based on a Lewis Structure) Wayne Breslyn (Dr. B.) 2024-09-18 | In this video, we'll learn how to use AXE notation to figure out the molecular geometry of different molecules. The AXE notation focuses on the central atom (A), the number of atoms bonded to it (X), and the number of lone pairs of electrons (E) on the central atom. Understanding these parts is key to determining the shape of any molecule. We'll work through four examples to show you exactly how this method is applied.Also, in this video, I’ll briefly mention another method called the steric number method, which can also help you figure out molecular geometry. You can find more information on that method here: youtu.be/Moj85zwdULgFor the AXE notation, the first step is to correctly draw the Lewis structure of the molecule. From the Lewis structure, we can easily identify the number of atoms attached to the central atom and the lone pairs. It's crucial to understand the difference between lone pairs and bonding pairs of electrons, as this affects the overall molecular shape.Lone Pair vs Bonding Pair Electrons: youtu.be/Ge1gKBmDIrwOnce we’ve figured out the AXE notation for a molecule, we can then reference a table of molecular geometries, such as the one available on Wikipedia, to determine its shape. I'll include a link here for quick access:en.wikipedia.org/wiki/VSEPR_theory#AXE_method
Is NaCl Dissolving Endothermic or Exothermic? Wayne Breslyn (Dr. B.) 2024-09-16 | In this video, we discuss how lattice energy and hydration energy affect the dissolving process of ionic compounds like sodium chloride (NaCL) in water. Breaking the ionic bonds (lattice energy) requires energy (endothermic), while the hydration of ions releases energy (exothermic). The overall temperature change depends on which energy is greater.While it is not covered in this video: ... predicting whether dissolution is endothermic or exothermic isn't always easy, but some general factors can help:Higher Charge and Smaller Ions: Ions with higher charges and smaller sizes typically have higher lattice energies, making them harder to dissolve. However, they also have higher hydration energies.Solubility Trends: Compounds that are highly soluble often have hydration energies that offset their lattice energies.
Dissociate vs Dissolve (Differences and Similarities) Wayne Breslyn (Dr. B.) 2024-09-12 | When a substance disperses uniformly in a liquid, we say that it is dissolving. Dissolving is the broader category that refers to a substance spreading out evenly throughout a solvent. Sometimes, however, we encounter dissociation. Dissociation occurs when a substance not only dissolves but also breaks apart into ions, which then disperse uniformly throughout the solution.Dissociation typically happens with ionic compounds, such as sodium chloride (NaCl). When NaCl dissolves in water, it dissociates into sodium ions (Na⁺) and chloride ions (Cl⁻). So, in this case, the substance dissolves and dissociates into ions.On the other hand, substances like table sugar (sucrose) also dissolve in water, spreading out uniformly, but they do not dissociate into ions. The sugar molecules remain intact, so we say that sugar dissolves but does not dissociate.In summary, dissolving is the broad process, and dissociation is a specific type of dissolving that involves breaking apart into ions.
How to Find the Mass Number of an Element Wayne Breslyn (Dr. B.) 2024-09-09 | In this video, we’ll explore the concept of finding the mass number of an element using the periodic table or when given protons and neutrons.The key idea is that if you have two of these pieces of information, you can figure out the third.We can use the periodic table to find the number of protons by looking at the atomic number above the element symbol. Mass Number = Protons + NeutronsYou may be given problems where you have the mass number and either the protons or neutrons and need to find the missing value. We’ll also address how to do this and talk about how the average atomic mass on the periodic table, found below the element symbol, relates to the mass number.
What Element Has 14 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 14 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 14 protons, we just look at the Atomic Number. When we do that, we see that Silicon (Si) is the element with 14 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What element has 10 protons 10 neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has ten protons and ten neutrons, we refer to the Periodic Table. Elements are organized by increasing Atomic Number, which indicates the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsWhen we check the Atomic Number, we see that Neon (Ne) is the element with ten protons. Therefore, Neon is the element we're looking for.Protons are positively charged particles that define the identity of an element, while neutrons add to the atom's mass. With ten neutrons, the total mass number is 20, corresponding to Neon-20, the most common isotope of Neon.More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
Is a pH of 5 an Acid, Base, or Neutral? Wayne Breslyn (Dr. B.) 2024-09-07 | pH is a measure of the acidity or alkalinity of a solution. It is measured on a logarithmic scale ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 indicate acidity, and values above 7 indicate alkalinity. To determine whether a pH of 5 is an acid, base, or neutral, we can refer to the pH scale. Here's a simplified version of the scale divided into acid, base, and neutral:Acidic:0 1 2 3 4 5 6Neutral:7Basic (Alkaline):8 9 10 11 12 13 14According to this scale, a pH of 5 is weakly acidic since it falls within the acidic range but is not too far from neutral.Examples of substances that are around a pH of 5 include:Black coffee: Black coffee typically has a pH of around 5, contributing to its slightly acidic taste.Normal rain: Clean rain has a pH of around 5.0 to 5.5 due to the presence of dissolved carbon dioxide, which forms carbonic acid.Bananas: Ripe bananas have a pH of around 4.5 to 5.2, placing them in the weakly acidic range.To determine the pH of a solution, you can use pH paper or electronic pH meters. pH paper is a simple and inexpensive option. You dip the pH paper into the solution, and the paper changes color based on the pH level. By comparing the color of the paper to the scale provided on the package, you can determine the approximate pH value.Electronic pH meters are more accurate but also more expensive. These devices consist of a probe that is immersed in the solution, and they provide a digital readout of the pH value. They are commonly used in scientific laboratories and industries where precise pH measurements are required.
Is a pH of 6 an Acid, Base, or Neutral? Wayne Breslyn (Dr. B.) 2024-09-07 | pH is a measure of the acidity or alkalinity of a solution. It is measured on a logarithmic scale ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 indicate acidity, and values above 7 indicate alkalinity. To determine whether a pH of 6 is an acid, base, or neutral, we can refer to the pH scale. Here's a simplified version of the scale divided into acid, base, and neutral:Acidic:0 1 2 3 4 5 6Neutral:7Basic (Alkaline):8 9 10 11 12 13 14According to this scale, a pH of 6 is weakly acidic since it falls within the acidic range but is close to neutral.Examples of substances that are around a pH of 6 include:Milk: Milk has a pH of around 6.5 to 6.7, making it slightly acidic.Urine: Normal human urine has a pH range of about 4.6 to 8.0, but the average is around 6.Black tea: Black tea typically has a pH of around 4.9 to 5.5, but it can vary depending on brewing time and other factors.To determine the pH of a solution, you can use pH paper or electronic pH meters. pH paper is a simple and inexpensive option. You dip the pH paper into the solution, and the paper changes color based on the pH level. By comparing the color of the paper to the scale provided on the package, you can determine the approximate pH value.Electronic pH meters are more accurate but also more expensive. These devices consist of a probe that is immersed in the solution, and they provide a digital readout of the pH value. They are commonly used in scientific laboratories and industries where precise pH measurements are required.
Convert 3.5 L to mL (3.5 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | uantity you want to convert (3.5 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (3.5 L) as a fraction over 1: 3.5 L / 1Multiply this fraction by the conversion factor: (3.5 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(3.5 * 1000) / (1 * 1) mL = 3500 / 1 mL = 3500 mLSo, 3.5 L is equivalent to 3500 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
Convert 4.5 L to mL (4.5 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 4.5 liters (L) to milliliters (mL), you can use the following steps. Note that the L will cancel out as you perform the conversion, leaving only mL:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Start with the quantity you want to convert (4.5 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (4.5 L) as a fraction over 1: 4.5 L / 1Multiply this fraction by the conversion factor: (4.5 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(4.5 * 1000) / (1 * 1) mL = 4500 / 1 mL = 4500 mLSo, 4.5 L is equivalent to 4500 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
Convert 460mmHg to atm. Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 460 millimeters of mercury (mmHg) to atmospheres (atm), you can use the conversion factor: 1 atmosphere (atm) is equal to 760 mmHg.The conversion formula is:Pressure in atmospheres (atm) = Pressure in millimeters of mercury (mmHg) / 760For your specific example:Pressure in atmospheres = 460 mmHg / 760Calculating this:Pressure in atmospheres is approximately 0.605 atmSo, 460 mmHg is approximately equal to 0.605 atmospheres.Essentially, we multiply the mmHg given by the conversion factor 1 atm/760 mmHg. The units mmHg cancel out leaving atm, which is what we are trying to find.It's important to note that atmospheric pressure varies with altitude. As you move to higher elevations, atmospheric pressure decreases. Therefore, the conversion factor may not be accurate at locations significantly above or below sea level.
Combined Gas Law Practice Problem: Find New Volume Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll tackle a combined gas law practice problem. We're given a gas sample with an initial volume, pressure, and temperature (in Celsius), and we'll calculate its new volume when the pressure and temperature change. Problem:A sample of gas has a volume of 15.0 L at a pressure of 1.00 atm and a temperature of 27.2 degrees Celsius. What is the new volume if the pressure is raised to 1580 mmHg and the temperature is raised to 356.2 K?This is a classic example of how to apply the combined gas law, derived from the ideal gas law, when you're given initial pressure, volume, and temperature, and asked to find the new volume under changed conditions. We'll walk through the solution step-by-step, including the necessary temperature conversion, ensuring you understand the process.
Combined Gas Law Practice Problem: Find New Temperature Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll work through another combined gas law problem, focusing on finding the final temperature of a gas when pressure and volume change. We'll emphasize the importance of ensuring units cancel out correctly during the calculation, a key step in solving gas law problems accurately.Problem:A gas initially at 2.00 atm, 1.20 L, and 273 K has its pressure reduced to 0.90 atm and the volume is increased to 3.1 L. Determine the final temperature.We'll use the combined gas law to solve for the unknown final temperature, given the initial and final pressure and volume conditions.
Combined Gas Law Practice Problem: Find New Volume (Constant Pressure) Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll solve a combined gas law problem where the pressure remains constant. This simplifies the combined gas law equation to V1/T1 = V2/T2, allowing us to focus on the relationship between volume and temperature.Problem:3.22 L of a gas is collected at 23.0° C. What will be its volume after it cools to 15.0° Celsius if the pressure remains constant?We'll use the simplified combined gas law equation to calculate the new volume, given the initial volume and temperature, and the final temperature. Remember, we'll need to convert temperatures to Kelvin before plugging them into the equation.
What element has 6 protons 8 neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has six protons and eight neutrons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number, which represents the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsSo, to figure out the element with six protons, we look at the Atomic Number, and we find that Carbon (C) is the element with six protons. This makes Carbon the element we're looking for.Remember, protons are positively charged particles in the nucleus that determine the identity of an element. While neutrons are important for the atom's mass, they don't affect the element's identity. In this case, the neutrons add up to a total mass number of 14, which corresponds to Carbon-14, a common isotope of Carbon.More Help:Protons, Neutrons, and Electrons for Elements: [YouTube link]Protons, Neutrons, and Electrons for Ions: [YouTube link]Rules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
What Element Has Six Protons and Seven Neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has six protons and seven neutrons, we need to refer to the Periodic Table. Elements on the table are arranged by increasing Atomic Number, which tells us the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsSo, to find the element with six protons, we simply look at the Atomic Number, and we discover that Carbon (C) is the element with six protons. This means Carbon is the element we're looking for.Protons are positively charged particles in the nucleus and determine the identity of the element. Neutrons, on the other hand, contribute to the atom's mass but do not change the element's identity. In this case, the seven neutrons give us a total mass number of 13, corresponding to Carbon-13, an isotope of Carbon.More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
What Element Has 12 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 12 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 12 protons, we just look at the Atomic Number. When we do that, we see that Magnesium (Mg) is the element with 12 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What Element Has 11 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 11 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 11 protons, we just look at the Atomic Number. When we do that, we see that Sodium (Na) is the element with 11 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What Element Has 10 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 10 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 10 protons, we just look at the Atomic Number. When we do that, we see that Neon (Ne) is the element with 10 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What element has 9 protons 10 neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has nine protons and ten neutrons, we refer to the Periodic Table. Elements on the table are arranged by increasing Atomic Number, which indicates the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsBy checking the Atomic Number, we see that Fluorine (F) is the element with nine protons. Therefore, Fluorine is the element we're looking for.Protons are positively charged particles that define the identity of an element, while neutrons add to the atom's mass. With ten neutrons, the total mass number is 19, corresponding to Fluorine-19, the most common isotope of Fluorine.More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
Is a pH of 9 an Acid, Base, or Neutral? Wayne Breslyn (Dr. B.) 2024-09-07 | pH is a measure of the acidity or alkalinity of a solution. It is measured on a logarithmic scale ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 indicate acidity, and values above 7 indicate alkalinity. To determine whether a pH of 9 is an acid, base, or neutral, we can refer to the pH scale. Here's a simplified version of the scale divided into acid, base, and neutral:Acidic:0 1 2 3 4 5 6 7Neutral:7Basic (Alkaline):8 9 10 11 12 13 14According to this scale, a pH of 9 is mildly basic (alkaline) since it falls within the basic range but is not too far from neutral.Examples of substances that are around a pH of 9 include:Baking soda: A solution of baking soda in water has a pH of around 9, making it slightly basic.Seawater: The pH of seawater is typically around 8 to 8.3, which is also mildly basic.Borax: Borax, a common household cleaner and laundry booster, has a pH of around 9.2.To determine the pH of a solution, you can use pH paper or electronic pH meters. pH paper is a simple and inexpensive option. You dip the pH paper into the solution, and the paper changes color based on the pH level. By comparing the color of the paper to the scale provided on the package, you can determine the approximate pH value.Electronic pH meters are more accurate but also more expensive. These devices consist of a probe that is immersed in the solution, and they provide a digital readout of the pH value. They are commonly used in scientific laboratories and industries where precise pH measurements are required.
Can You Have a pH less than one? Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll explore whether it's possible to have a pH less than one. pH is defined as the negative log of the concentration of the hydronium ion (pH = -log[H₃O⁺]). We'll try different pH levels and take a closer look at concentrated hydrochloric acid, which you can buy at 12 molar. When we calculate the pH of a 12 M solution of HCl, we find that it is indeed possible to have a pH less than one.
Balancing Redox Reactions: Cu + Ag+ → Cu2+ + Ag Wayne Breslyn (Dr. B.) 2024-09-07 | This video demonstrates how to balance the redox reaction:Cu + Ag⁺ → Cu²⁺ + AgWe'll break down:Oxidation: Copper (Cu) is oxidized, losing two electrons and increasing its oxidation state from 0 to +2Reduction: Silver ions (Ag+) are reduced, gaining one electron and decreasing their oxidation state from +1 to 0Electron Flow: Electrons flow from copper (Cu) to silver ions (Ag+)Oxidizing Agent: Silver ions (Ag+) act as the oxidizing agent, accepting electrons from copperReducing Agent: Copper (Cu) acts as the reducing agent, donating electrons to silver ionsBy the end of this video, you'll have a clear understanding of how to analyze and balance redox reactions, a crucial skill in chemistry!
Convert 510mmHg to atm. Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 510 millimeters of mercury (mmHg) to atmospheres (atm), you can use the conversion factor: 1 atmosphere (atm) is equal to 760 mmHg.The conversion formula is:Pressure in atmospheres (atm) = Pressure in millimeters of mercury (mmHg) / 760For your specific example:Pressure in atmospheres = 510 mmHg / 760Calculating this:Pressure in atmospheres is approximately 0.671 atmSo, 510 mmHg is approximately equal to 0.671 atmospheres.Essentially, we multiply the mmHg given by the conversion factor 1 atm/760 mmHg. The units mmHg cancel out, leaving atm, which is what we are trying to find.It's important to note that atmospheric pressure varies with altitude. As you move to higher elevations, atmospheric pressure decreases. Therefore, the conversion factor may not be accurate at locations significantly above or below sea level.
What does the arrow mean in chemistry? Wayne Breslyn (Dr. B.) 2024-09-07 | In Chemistry, the Arrow in symbol signifies irreversible chemical reactions. Each one of these symbols comes up in general chemistry multiple times of the course of a semester. Knowing how each type of arrow relates to chemistry is a key skill.Arrow in Chemistry Signifies Irreversible Reactions:The arrow (→) in chemistry denotes an irreversible chemical reaction. This means that reactants change completely into products, and the reaction progresses in one direction only.Dynamic Equilibrium Arrows (⇌):Equilibrium arrows (⇌) indicate a dynamic balance in chemical reactions. They represent situations where reactants can convert into products, and products can revert to reactants. This reflects a state where the forward and reverse reactions occur at equal rates.Resonance Arrows (↔) and Multiple Lewis Structures:In organic chemistry, resonance arrows (↔) are used to illustrate resonance structures. These arrows do not imply a back-and-forth transition but show that multiple valid Lewis structures can be drawn for a molecule.The real structure is a hybrid of these equivalent resonance structures. This concept is particularly relevant when dealing with compounds containing double bonds or lone pairs.Join this channel to get full access to Dr. B's chemistry guides:youtube.com/channel/UCaUF73YX-uQTGwDB20I3n3g/join
Convert 5.5 L to mL (5.5 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 5.5 liters (L) to milliliters (mL), you can use the following steps. Note that the L will cancel out as you perform the conversion, leaving only mL:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Start with the quantity you want to convert (5.5 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (5.5 L) as a fraction over 1: 5.5 L / 1Multiply this fraction by the conversion factor: (5.5 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(5.5 * 1000) / (1 * 1) mL = 5500 / 1 mL = 5500 mLSo, 5.5 L is equivalent to 5500 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
What Element Has 30 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 30 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 30 protons, we just look at the Atomic Number. When we do that, we see that Zinc (Zn) is the element with 30 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What Element Has 9 Protons and 11 Neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has nine protons and eleven neutrons, we need to look at the Periodic Table. Elements on the table are organized by increasing Atomic Number, which represents the number of protons in an atom's nucleus.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsWhen we check the Atomic Number, we find that Fluorine (F) is the element with nine protons. This means Fluorine is the element we are looking for.Protons, which are positively charged particles, determine the identity of an element, while neutrons contribute to the atom's mass. In this case, with eleven neutrons, the total mass number is 20, corresponding to Fluorine-20, an isotope of Fluorine.More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
Is a pH of 7 an Acid, Base, or Neutral? Wayne Breslyn (Dr. B.) 2024-09-07 | pH is a measure of the acidity or alkalinity of a solution. It is measured on a logarithmic scale ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 indicate acidity, and values above 7 indicate alkalinity. To determine whether a pH of 7 is an acid, base, or neutral, we can refer to the pH scale. Here's a simplified version of the scale divided into acid, base, and neutral:Acidic:0 1 2 3 4 5 6Neutral:7Basic (Alkaline):8 9 10 11 12 13 14According to this scale, a pH of 7 is neutral. It sits right in the middle of the scale, indicating a balance between acidity and alkalinity.Examples of substances that are around a pH of 7 include:Pure water: Pure water has a pH of 7, making it perfectly neutral.Human blood: The pH of human blood is tightly regulated around 7.4, which is slightly alkaline but close to neutral.Saliva: Saliva typically has a pH between 6.5 and 7.4, falling within the near-neutral range.To determine the pH of a solution, you can use pH paper or electronic pH meters. pH paper is a simple and inexpensive option. You dip the pH paper into the solution, and the paper changes color based on the pH level. By comparing the color of the paper to the scale provided on the package, you can determine the approximate pH value.Electronic pH meters are more accurate but also more expensive. These devices consist of a probe that is immersed in the solution, and they provide a digital readout of the pH value. They are commonly used in scientific laboratories and industries where precise pH measurements are required.
Combined Gas Law Practice Problem: Find New Temperature (Constant Volume) Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll explore a combined gas law problem where the volume remains constant. This simplifies the combined gas law equation to P1/T1 = P2/T2, focusing on the relationship between pressure and temperature.Problem:For a gas in a closed container, the pressure is increased from 11.0 atmospheres to 12.2 atmospheres. The original temperature was 25.0 degrees Celsius. What is the final temperature of the gas?We'll utilize the simplified combined gas law equation to determine the final temperature, given the initial and final pressures and the initial temperature. Don't forget to convert the initial temperature to Kelvin!
Convert 530mmHg to atm. Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 530 millimeters of mercury (mmHg) to atmospheres (atm), you can use the conversion factor: 1 atmosphere (atm) is equal to 760 mmHg.The conversion formula is:Pressure in atmospheres (atm) = Pressure in millimeters of mercury (mmHg) / 760For your specific example:Pressure in atmospheres = 530 mmHg / 760Calculating this:Pressure in atmospheres is approximately 0.697 atmSo, 530 mmHg is approximately equal to 0.697 atmospheres.Essentially, we multiply the mmHg given by the conversion factor 1 atm/760 mmHg. The units mmHg cancel out, leaving atm, which is what we are trying to find.It's important to note that atmospheric pressure varies with altitude. As you move to higher elevations, atmospheric pressure decreases. Therefore, the conversion factor may not be accurate at locations significantly above or below sea level.
Convert 6.5 L to mL (6.5 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 6.5 liters (L) to milliliters (mL), you can use the following steps. Note that the L will cancel out as you perform the conversion, leaving only mL:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Start with the quantity you want to convert (6.5 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (6.5 L) as a fraction over 1: 6.5 L / 1Multiply this fraction by the conversion factor: (6.5 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(6.5 * 1000) / (1 * 1) mL = 6500 / 1 mL = 6500 mLSo, 6.5 L is equivalent to 6500 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
What Element Has 47 Protons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has 47 protons, we need to look at the Periodic Table. The elements on the Periodic Table are organized by increasing Atomic Number (the number above the element symbol). What is helpful is that the Atomic Number equals the number of protons for an element:Atomic Number = Number of ProtonsVideo: How to Find the Atomic Number for an Element:youtu.be/P1YNqvQxuZEIn fact, the Atomic Number is sometimes called the Proton Number. So to figure out the element with 47 protons, we just look at the Atomic Number. When we do that, we see that Silver (Ag) is the element with 47 protons.Note that protons are positively charged particles found in the nucleus of an atom.
What element has 11 protons 12 neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has eleven protons and twelve neutrons, we refer to the Periodic Table. Elements are arranged by increasing Atomic Number, which indicates the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsWhen we check the Atomic Number, we find that Sodium (Na) is the element with eleven protons. So, Sodium is the element we're looking for.Protons are positively charged particles that define the identity of an element, while neutrons contribute to the atom's mass. In this case, with twelve neutrons, the total mass number is 23, corresponding to Sodium-23, the most common isotope of Sodium.More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
What Element Has Six Protons and Six Neutrons? Wayne Breslyn (Dr. B.) 2024-09-07 | To determine which element has six protons and six neutrons, we turn to the Periodic Table. The elements are arranged by increasing Atomic Number, which tells us the number of protons in the nucleus of an atom.The Atomic Number equals the number of protons for an element: Atomic Number = Number of ProtonsBy looking at the Atomic Number, we find that Carbon (C) is the element with six protons. So Carbon is the element we are looking for.Protons are positively charged particles that determine the identity of an element, while neutrons contribute to the atom's mass. In this case, with six neutrons, the total mass number is 12, which corresponds to Carbon-12, the most common isotope of Carbon.More Help:More HelpProtons, Neutrons, and Electrons for Elements: youtu.be/4PU-2TWEp5EProtons, Neutrons, and Electrons for Ions: youtu.be/HkQEDntUK0URules:Atomic Number = Number of ProtonsNumber of Protons = Number of Electrons (for a neutral element)Mass Number = Number of Protons + Neutrons
Which has a Larger Atomic Radius, Ca or F? Wayne Breslyn (Dr. B.) 2024-09-07 | We can determine which atom has a larger atomic radius, Ca or F, by looking at trends on the Periodic Table. When we look at Calcium and Fluorine we see that F if much further to the right of the Periodic Table. As we go across a period on the Periodic Table the atomic radius decreases. Ca is also lower than F in its group. Therefore, Ca is larger than F. General Trends for Atomic Radii (atomic size)Atomic Radius Decreases Across a Period: As you move from left to right across a period (horizontal row) of the periodic table, atomic radius generally decreases. This trend occurs because as you move across a period, the number of protons in the nucleus increases, resulting in a stronger attractive force on the electrons. The increased positive charge pulls the electron cloud closer to the nucleus, leading to a smaller atomic radius.Atomic Radius Increases Down a Group: As you move down a group (vertical column) of the periodic table, atomic radius generally increases. This trend occurs because each new row in the periodic table adds a new electron shell, further away from the nucleus. The additional electron shells shield the outermost electrons from the attractive force of the nucleus, causing the atomic radius to increase.Cations have Smaller Radii than their Parent Atoms: When an atom loses one or more electrons to form a cation, the resulting ion has a smaller atomic radius than its parent atom. This is because the loss of electrons reduces the electron-electron repulsion, causing the remaining electrons to be pulled closer to the nucleus. The reduction in electron-electron repulsion leads to a smaller atomic radius for cations.Anions have Larger Radii than their Parent Atoms: Conversely, when an atom gains one or more electrons to form an anion, the resulting ion has a larger atomic radius than its parent atom. The addition of extra electrons increases the electron-electron repulsion, causing the electron cloud to expand. The increased electron-electron repulsion results in a larger atomic radius for anions.Based on these general trends we can say that Ca is larger than F.
Is a pH of 8 an Acid, Base, or Neutral? Wayne Breslyn (Dr. B.) 2024-09-07 | pH is a measure of the acidity or alkalinity of a solution. It is measured on a logarithmic scale ranging from 0 to 14. A pH of 7 is considered neutral, while values below 7 indicate acidity, and values above 7 indicate alkalinity. To determine whether a pH of 8 is an acid, base, or neutral, we can refer to the pH scale. Here's a simplified version of the scale divided into acid, base, and neutral:Acidic:0 1 2 3 4 5 6 7Neutral:7Basic (Alkaline):8 9 10 11 12 13 14According to this scale, a pH of 8 is mildly basic (alkaline) since it falls within the basic range but is close to neutral.Examples of substances that are around a pH of 8 include:Seawater: The pH of seawater is typically around 8 to 8.3, which is slightly basic.Baking soda solution: A slightly more concentrated solution of baking soda in water can have a pH closer to 8.Some antacids: Certain antacids are formulated to have a pH around 8 to help neutralize stomach acid.To determine the pH of a solution, you can use pH paper or electronic pH meters. pH paper is a simple and inexpensive option. You dip the pH paper into the solution, and the paper changes color based on the pH level. By comparing the color of the paper to the scale provided on the package, you can determine the approximate pH value.Electronic pH meters are more accurate but also more expensive. These devices consist of a probe that is immersed in the solution, and they provide a digital readout of the pH value. They are commonly used in scientific laboratories and industries where precise pH measurements are required.
Can you have a pH of 0? Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we explore the question: Is it possible to have a pH of zero? The pH of a solution is calculated using the formula pH = -log[H₃O⁺], where [H₃O⁺] represents the concentration of hydronium ions. Understanding this relationship is key to determining how low a pH can go.To put this to the test, we experiment with a one molar solution of a strong acid. When we plug the concentration into the formula, the result is revealing: the negative log of 1 equals zero. This demonstrates that a one molar solution can indeed have a pH of zero.
Balancing Redox Reactions: Al + Fe2+ → Al3+ + Fe Wayne Breslyn (Dr. B.) 2024-09-07 | This video demonstrates how to balance the redox reaction:Al + Fe²⁺ → Al³⁺ + FeWe'll break down:Oxidation: Aluminum (Al) is oxidized, losing three electrons and increasing its oxidation state from 0 to +3Reduction: Iron ions (Fe2+) are reduced, gaining two electrons and decreasing their oxidation state from +2 to 0Electron Flow: Electrons flow from aluminum (Al) to iron ions (Fe2+)Oxidizing Agent: Iron ions (Fe2+) act as the oxidizing agent, accepting electrons from aluminumReducing Agent: Aluminum (Al) acts as the reducing agent, donating electrons to iron ionsBy the end of this video, you'll have a clear understanding of how to analyze and balance redox reactions, a crucial skill in chemistry!:
Balancing the Redox Reaction: Zn + Cu 2+ → Zn 2+ + Cu Wayne Breslyn (Dr. B.) 2024-09-07 | This video demonstrates how to balance the redox reaction:Zn + Cu²⁺ → Zn²⁺ + CuWe'll break down:Oxidation: Zinc (Zn) is oxidized, losing two electrons and increasing its oxidation state from 0 to +2Reduction: Copper ions (Cu²⁺) are reduced, gaining two electrons and decreasing their oxidation state from +2 to 0Electron Flow: Electrons flow from zinc (Zn) to copper ions (Cu²⁺)Oxidizing Agent: Copper ions (Cu²⁺) act as the oxidizing agent, accepting electrons from zincReducing Agent: Zinc (Zn) acts as the reducing agent, donating electrons to copper ionsBy the end of this video, you'll have a clear understanding of how to analyze and balance simple redox reactions.
Combined Gas Law Practice Problem: Find New Volume Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll tackle another combined gas law practice problem where we'll calculate the new volume of a gas under changed temperature conditions.Problem:A balloon has a volume of 3.5 L at STP (Standard Temperature and Pressure). What will the new volume be if the balloon is taken outside on a day where the temperature is -17.15° Celsius? Assume the pressure inside and outside the balloon remains constant at 1.0 atm.We're given the initial volume and the change in temperature, with pressure held constant. We'll use the combined gas law to solve for the new volume.
Convert 590mmHg to atm. Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 590 millimeters of mercury (mmHg) to atmospheres (atm), you can use the conversion factor: 1 atmosphere (atm) is equal to 760 mmHg.The conversion formula is:Pressure in atmospheres (atm) = Pressure in millimeters of mercury (mmHg) / 760For your specific example:Pressure in atmospheres = 590 mmHg / 760Calculating this:Pressure in atmospheres is approximately 0.776 atmSo, 590 mmHg is approximately equal to 0.776 atmospheres.Essentially, we multiply the mmHg given by the conversion factor 1 atm/760 mmHg. The units mmHg cancel out, leaving atm, which is what we are trying to find.It's important to note that atmospheric pressure varies with altitude. As you move to higher elevations, atmospheric pressure decreases. Therefore, the conversion factor may not be accurate at locations significantly above or below sea level.
Convert 7.0 L to mL (7 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 7 liters (L) to milliliters (mL), you can use the following steps. Note that the L will cancel out as you perform the conversion, leaving only mL:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Start with the quantity you want to convert (7 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (7 L) as a fraction over 1: 7 L / 1Multiply this fraction by the conversion factor: (7 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(7 * 1000) / (1 * 1) mL = 7000 / 1 mL = 7000 mLSo, 7 L is equivalent to 7000 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
Convert 6.0 L to mL (6 Liters to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 6 liters (L) to milliliters (mL), you can use the following steps. Note that the L will cancel out as you perform the conversion, leaving only mL:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Start with the quantity you want to convert (6 L) and set up a ratio where the original unit (L) is in the denominator and the target unit (mL) is in the numerator, using the conversion factor:Conversion factor: 1000 mL / 1 LWrite the quantity you want to convert (6 L) as a fraction over 1: 6 L / 1Multiply this fraction by the conversion factor: (6 L / 1) * (1000 mL / 1 L)Notice that the units of liters (L) in the numerator and denominator cancel out, leaving only the units of milliliters (mL):(6 * 1000) / (1 * 1) mL = 6000 / 1 mL = 6000 mLSo, 6 L is equivalent to 6000 milliliters. The units of liters cancel out during the conversion process, leaving only milliliters as the final unit.
Convert 1 L to mL (1 Liter to Milliliters) Wayne Breslyn (Dr. B.) 2024-09-07 | To convert 1 liter (L) to milliliters (mL), it's essential to remember that the core conversion factor is quite straightforward: 1 liter is equivalent to 1000 milliliters. Once memorized, it greatly simplifies the conversion of other amounts of liters or milliliters between each other:Conversion Factor:1 liter (L) = 1000 milliliters (mL)Knowing this, to convert 1 L into mL, you can apply this conversion factor directly:Conversion factor: 1000 mL / 1 LWith the quantity you want to convert being (1 L), the conversion process is direct and does not require the setup of complex ratios or fractions. You directly use the conversion factor:1 L = 1000 mLTherefore, converting 1 L to mL is straightforward with the understanding that 1 liter directly translates to 1000 milliliters without the need for additional calculations. This conversion factor is a key piece of knowledge that aids in the conversion of various volumes from liters to milliliters and vice versa.
Is Chlorine (Cl) Paramagnetic or Diamagnetic? Wayne Breslyn (Dr. B.) 2024-09-07 | In this video, we'll investigate whether Chlorine (Cl) is paramagnetic or diamagnetic. We'll examine its electron configuration and orbital diagram to make the determination.Key concepts covered:Electron configuration: We'll look at Chlorine's electron configuration, which ends in 3p5, indicating an unpaired electron in its 3p sublevel.Orbital diagram: We'll use an orbital diagram to visualize the distribution of electrons in Chlorine's orbitals, clearly showing this unpaired electron in the 3p sublevel.Paramagnetic vs. diamagnetic: The presence of this unpaired electron is what leads to Chlorine's paramagnetic behavior.
