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STP, Volume Ratios, Energy in Reactions, and Limiting Reagents Chapter 4 SABIS Grade 10 Part 4 STP, Volume Ratios, Energy in Reactions, and Limiting Reagents ✅ Lesson 19: ✅ STP, Volume Ratios, Energy in Reactions, and Limiting Reagents Hello learners! 🌞🎒 Today's chemistry class is going to be a thrilling ride as we explore concepts like Standard Temperature and Pressure (STP), stoichiometric calculations, and limiting reagents. Buckle up and get ready! 🚀🔬💡 Prerequisite Material Quiz 📚🧠 What does STP stand for? What are the conditions for STP? True or False: At STP, 1.00 mole of any gas occupies 22.4 dm³. How much percentage of air is oxygen gas by volume? What is a limiting reagent in a chemical reaction? Can the volume ratio at STP be used for any given reaction equation? True or False: The limiting reagent determines how much of the other reactants will be consumed in a chemical reaction. Can we write an equation including the energy required or released? True or False: A limiting reagent gets completely used up in a chemical reaction. Can we solve problems using the volume ratio? (Answers at the end of the lesson) Explanation: STP, Volume Ratios, Energy in Reactions, and Limiting Reagents 🧐👩🔬 Standard Temperature and Pressure (STP) STP is a common set of conditions for gases defined as 0 degrees Celsius and 1.00 atmosphere pressure. Under these conditions, any gas will have a volume of 22.4 dm³ per mole. Volume Ratios In gas reactions at STP, the volumes of gases involved can be directly related to the coefficients in the balanced equation. These are the volume ratios. Energy in Reactions Chemical reactions either absorb or release energy. We can represent this energy change in the chemical equation. Limiting Reagents In a chemical reaction, the limiting reagent is the substance that gets completely consumed and determines the maximum amount of product that can be formed. Examples 🌍🔬🔎 STP and volume ratios : In the reaction 2H₂(g) + O₂(g) → 2H₂O(g), the volume ratio of hydrogen to oxygen to water vapor is 2:1:2. If we start with 44.8 dm³ of hydrogen gas at STP, we would expect to produce 44.8 dm³ of water vapor, assuming oxygen is not the limiting reagent. Energy in reactions : In the combustion of methane (exothermic reaction), energy is released: CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g) + energy. Limiting reagents : If we react 4 moles of hydrogen gas with 1 mole of nitrogen gas according to the equation N₂(g) + 3H₂(g) → 2NH₃(g), hydrogen is the limiting reagent. It will be completely consumed and determine the maximum amount of ammonia that can be produced (2 moles). Post-lesson MCQs 📝✅ True or False: At STP, all gases have the same volume per mole. What is the volume ratio of hydrogen to oxygen in the balanced equation for the formation of water? Can energy be a product in a chemical reaction? True or False: The limiting reagent in a reaction is always the reactant with the smallest amount of moles. How do we determine the mass of the excess reagent left in a reaction? (Answers at the end of the lesson) Answers Prerequisite Material Quiz : Standard Temperature and Pressure, 0 degrees Celsius and 1.00 atmosphere pressure, True, 20%, The substance that gets completely consumed in a reaction, Yes, True, Yes, True, Yes. Post-lesson MCQs : True, 2:1, Yes, energy can be a product in exothermic reactions, False, the limiting reagent is the substance that is completely consumed in a reaction, not necessarily the one with the smallest amount of moles, By subtracting the amount of the reagent that reacted from the total amount initially present. Complete the Questions : The volume ratio at STP for a given reaction equation is directly related to the coefficients of the gases in the balanced equation. An example of an endothermic reaction is the thermal decomposition of calcium carbonate: CaCO₃(s) + energy → CaO(s) + CO₂(g). The volume of 2 moles of nitrogen gas at STP is 2 moles × 22.4 dm³/mole = 44.8 dm³. Stoichiometric calculations involve using the coefficients in a balanced equation to calculate quantities of reactants or products. It can involve mole, mass, volume, or energy ratios. The limiting reagent is determined by comparing the amount of products each reactant could produce if it were completely consumed. The reactant that produces the least amount of product is the limiting reagent.

Lesson 33 Chapter 6 SABIS Grade 10 Part 3 Lesson 33 231. Demonstration: Sublimation: Examples of solids that can sublime at room temperature: 1) Solid iodine, I2 (s) 2) Dry ice or solid carbon dioxide CO2 (s) 3) Any ammonium compound as ammonium chloride, NH4Cl and ammonium bromide, NH4Br232. Demonstration: Simple Distillation233. Demonstration: Fractional distillation. Discuss briefly: fractional distillation of liquefied air and fractional distillation of crude oil.234. Demonstration: Separating funnel235. Adsorption: means sticking to the surface.236. Adsorption: sticking of the particles of one material on the surface of another. Examples of adsorbing substances: Silica gel: adsorbs water vapor, Charcoal: adsorbs gases with strong odor and removes colored impurities from a solution237. Demonstration: Chromatography. It is the technique used to separate different compounds, especially those that can be easily destroyed by heat or chemicals. It can be used to separate colored components as: 1) Green liquid obtained by squashing green leaves. 2) Black ink. The property that carries the liquid up the paper is capillary action.238. Demonstration: Crystallization239. Alcohol is flammable, therefore it cannot be heated directly. To heat alcohol, we should use a steam bath or an electric heater.240. If you need to collect sugar from sugar alcohol solution heat the solution using an electric heater to crystallization point. Leave the solution to cool and crystals to form. Filter off the crystals.241. Vapor pressure and temperature are proportional NOT directly proportional. At the same temperature, the vapor pressure is the SAME. For the same liquid, the only factor affecting the pressure of the liquid is the temperature.242. Minimum conditions for liquid molecules to vaporize: 1) Molecules are supposed to be on the surface. 2) Molecules are supposed to have an average kinetic energy greater than the energy keeping the molecules in the liquid state.243. Water has a vapor pressure of 17.5 mmHg at 20oC. Which of the following will increase the vapor pressure of water? a) Transferring water to a larger container. b) Cooling water to 10oC c) Taking the container to the top of the mountain. d) Heating the water to 32oC244. Boiling point: is the temperature at which the liquid vaporizes anywhere in the solution.245. At the boiling point: a. Vapor pressure is equal to the surrounding pressure. b. Bubbles of vapor can form anywhere within the liquid. c. Molecules escape from the surface of the liquid to enter the gas phase as vapor (this also happens at room temperature). d. With increasing altitude, atmospheric pressure decreases and so does boiling point.246. Normal boiling point: is the temperature at which the vapor pressure is exactly 1 atm or 760 mmHg.247. Molar heat of fusion: is the energy required to change one mole of a substance from solid to liquid at the same temperature and constant pressure.248. General equation for Molar heat of vaporization: X (l) + heat ⇌ X (g)249. General equation for Molar heat of condensation: X (g) ⇌ X (l) + heat250. In general, a substance that has a higher boiling point is expected to have a Here are the points from 251 to 260:251. An aqueous solution is one in which the solvent is water.252. Salt and water is an example of aqueous solutions where the solute is a solid.253. Alcohol and water is an example of aqueous solutions where the solute is a liquid.254. Ammonia and water is an example of aqueous solutions where the solute is a gas.255. Concentration: relative amounts of solute and solvent.256. Molar concentration (Molarity): is the number of moles of solute per liter (dm3) of solution. (the relative amounts of solute and solution)257. Concentration of a given solution does not change if solution is split into fractions.258. Relationships between n, V, C and m, M, V, C: n = CV, 𝐂 = 𝐦/𝐕, 𝐕 = 𝐦/𝐂, m = n × M, m = CVM, 𝐌 = 𝐦/𝐂𝐕259. Preparing solutions with given concentrations.260. A 2 L bottle of 0.35 M solution is split into ten containers of 100ml capacity. What is the concentration of the solution in each of the new containers? a) 0.75 M b) 0.0035 M c) 2.0 M d) 0.35 M e) 100 M

eb67a2ec-f742-4749-a7e5-807f3a033701 A stable compound has a low level of potential energy. Summary

d2c57db7-7310-4eec-8c96-0767e3e76e39 Chemical Summary Relating to chemistry or chemicals.

Chapter 5 SABIS Grade 10 Lesson 5 Lesson 29 Part 5: A Closer Look at Effusion, Diffusion and Gas Behavior 👀💨🎈🌬 179. Effusion 💨: Let's imagine you're inflating a balloon but it has a tiny hole. The gas escaping from this hole is an example of effusion. It's basically the passage of a gas through a small opening. If you've ever heard a balloon slowly hissing as it deflates, that's effusion at work! SQ36 🎈💨 180 - 182. Kinetic Energies and Gases ⚡🔥: At the same temperature, the average kinetic energy (KE) of all ideal gases is the same. Crazy, right? This energy is directly proportional to the absolute temperature (KE = kT). Also, the KE is directly proportional to the gas's molar mass and inversely proportional to the gas velocity squared. Simply put, the lighter a particle is, the faster it moves (and the faster it effuses). 🏃♂️💨 SQ 37, 38 183 - 186. Speed of Gases and Kinetic Energy Comparisons 🏎💨: When comparing the speed of different gases at the same temperature, we use this equation: ν1/ν2 = √(M2/M1) And when comparing the time required for two different gases to travel the same distance, we use this one: t2/t1 = √(M2/M1) Lastly, when comparing the kinetic energy of gases at different temperatures, we use: KE1/KE2 = T1/T2 Don't worry, we'll go through examples of these. BQ17 🕓🔁 Exercise Time 🏋️♀️💡: It's time to flex your brain muscles! Try to solve these exercises based on what you've learned so far. Once you're done, check your answers to see if you got them right. If not, don't worry - just go through the lesson again. Remember, practice makes perfect! 🏅📚 10 cm³ of Helium gas took 5.0s to effuse (diffuse from a small orifice) under certain conditions of temperature and pressure. Under the same conditions, it took another gas X 20.0s to effuse from the same orifice. Calculate the molar mass of gas X. Explain all your calculations. 📝🤔 Which gas should diffuse faster, SO2 or CH4? How many times as fast? Why? 💨🔍 The rate of diffusion of a particular gas was measured and found to be 24 cm³/min. Under the same conditions, the rate of diffusion of methane gas CH4 was found to be 47.8 cm³/min. What is the molar mass of the unknown gas? ⏱📊 The molecules of an unknown gas, SOx, travel at 1⁄4 the speed (on average) of helium atoms at the same temperature. Calculate the molecular mass of SOx, and deduce the value of x. [O = 16; S = 32]. 🎈🔬 Cooking gas is a mixture of two gases: propane (C3H8) and butane (C4H10). On average, the molecules of which gas have a higher kinetic energy? On average, the molecules of which gas are moving faster? How much faster? 🔥🍳 187. A Quantitative Investigation of the Reaction of Magnesium Metal with Hydrochloric Acid 🧪🧑🔬: This part takes us back to chemistry class! Let's react magnesium (Mg) with hydrochloric acid (HCl). The reaction produces magnesium chloride (MgCl2) and hydrogen gas (H2). Here's what it looks like: Mg (s) + 2 HCl (aq) → MgCl2 (aq) + H2 (g) Observations during this reaction include the magnesium ribbon dissolving, effervescence due to the evolution of hydrogen gas, and the gas measuring cylinder tube becoming warm. When the H2 gas is produced, it's collected in a gas measuring tube. We have a set of instructions to properly read the volume of the gas and to determine its pressure. 188. Diffusion 🌬: Now, let's not confuse effusion with diffusion! Diffusion is the term used to describe the mixing of gases. Imagine spraying perfume in one corner of your room. After a while, you start to smell it everywhere in the room. That's diffusion at work! It's the process of the spread of a gas throughout space. BQ16 Stay tuned for the next lesson where we'll put these principles to use with more real-world examples and exercises! 🌍🌟 Quiz Time: Test Your Gas Laws Knowledge! 📝🎯🎉 Let's see how well you've absorbed the knowledge! Answer these multiple-choice questions based on the lesson. You're doing a great job, and it's almost time to celebrate! 🎉💡 What is Effusion? a) Mixing of gases b) Gas escaping through a small opening c) Gas transforming into a liquid d) Increase in pressure of a gas The average kinetic energy of an ideal gas is directly proportional to what? a) The gas's volume b) The absolute temperature c) The gas's pressure d) The gas's molar mass If two gases are at the same temperature, which gas's molecules will move faster? a) The one with the higher molar mass b) The one with the lower molar mass c) Both will move at the same speed d) There is not enough information to determine What is the difference between Effusion and Diffusion? a) Effusion is faster than Diffusion b) Diffusion is the process of gas escaping through a small opening while Effusion is the mixing of gases c) Effusion is the process of gas escaping through a small opening while Diffusion is the mixing of gases d) There is no difference, they are the same process In the reaction of magnesium with hydrochloric acid, what gas is produced? a) Oxygen b) Nitrogen c) Hydrogen d) Carbon Dioxide Good luck! Remember to refer back to the lesson if you're unsure about any of the answers. And most importantly, have fun! 😃👍 💡 Pro Tip: Applying the 70% Rule - Remember, it's better to get 7 out of 10 questions right than to guess all of them without understanding. Always strive to truly understand at least 70% of the material. 🧠💪 Answers: b) Gas escaping through a small opening b) The absolute temperature b) The one with the lower molar mass c) Effusion is the process of gas escaping through a small opening while Diffusion is the mixing of gases c) Hydrogen Keep learning and stay curious! The world of science is full of fascinating phenomena just waiting to be discovered. 🌟🔭📚👩🔬 Go to Chapter Test

028b3bc8-0c34-4f9d-add6-e470d7ab1324 As the atomic # of noble gases increases, their boiling and melting points increase. Summary

e394f9ea-c774-4aa0-9a78-77b4d1d2d00a Rewrite equations using ΔH notation per mole of a given reactant or product Summary When rewriting equations using ΔH notation, we express the enthalpy change (ΔH) per mole of a given reactant or product. This notation allows us to specify the heat energy associated with a specific amount of substance participating in a reaction and provides a standardized way to compare the energy changes between different reactions. To rewrite an equation using ΔH notation, we first determine the ΔH value for the reaction as it is originally written. This value represents the total enthalpy change for the entire reaction, typically measured in kilojoules (kJ) per mole of reaction. Next, we identify the reactant or product for which we want to express the ΔH notation per mole. This could be any substance involved in the reaction, and we focus on that particular component to calculate the ΔH value per mole. To express the ΔH notation per mole of the given reactant or product, we divide the total ΔH value by the stoichiometric coefficient of the reactant or product in the balanced chemical equation. This division accounts for the molar ratio between the reactant or product of interest and the overall reaction. For example, let's consider the reaction: 2H2(g) + O2(g) → 2H2O(g) ΔH = -483.6 kJ If we want to express the ΔH notation per mole of oxygen (O2), we divide the total ΔH value (-483.6 kJ) by the coefficient of O2 in the balanced equation, which is 1. This gives us ΔH = -483.6 kJ/mol O2. Similarly, if we want to express the ΔH notation per mole of water (H2O), we divide the total ΔH value by the coefficient of H2O, which is also 1 in this case. Thus, ΔH = -483.6 kJ/mol H2O. It's important to note that ΔH notation per mole allows for easy comparison of energy changes between reactions involving different amounts of substances. By normalizing the enthalpy change to a per-mole basis, we can directly compare the energy transformations associated with different reactions. By using ΔH notation per mole, we can assess the heat energy involved in specific reactants or products and understand their individual contributions to the overall energy change in a reaction. This notation provides a standardized and convenient way to express and analyze energy changes in chemical reactions. In summary, when rewriting equations using ΔH notation per mole of a given reactant or product, we divide the total ΔH value by the stoichiometric coefficient of the component of interest. This allows us to express the enthalpy change per mole and facilitates comparisons between reactions. ΔH notation per mole provides a standardized approach to quantifying the energy changes associated with specific reactants or products in chemical reactions. Regenerate response

e17599df-521c-43ef-9f72-2d55d12f5fe7 cheat sheet ap chemistry unit 6 https://k-chemistry.my.canva.site/ap-chemistry-unit-6-cheat-sheet-creation Summary

efa39b20-ac5a-491f-b078-49dc734f70c8 Hess's Law Definition Summary Hess’s Law states that: This means that whether the reaction takes place in one or two steps, the total enthalpy change of the reaction will still be the same

653e3bb2-bc02-474b-8c4f-2f3943af0cde Oxidation Numbers Rules Click the link for the interactive lesson https://examprepnotes.com/oxidation-numbers-lesson-plan Summary

Problems on Chapter 4 Chapter 4 SABIS Grade 10 Problems Problems on Chapter 4 📝 Lesson 24 📝 Summary Basic Ideas Problems 1. Stoichiometry and Mole-to-Mole Ratio: - Find the number of moles of products formed from a given number of moles of reactants. - Find the number of moles of reactant needed to form a given number of moles of product. Easy Questions: If 2 moles of hydrogen (H2) react with 1 mole of oxygen (O2) to form water (H2O), how many moles of water will be produced? In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), if 1 mole of nitrogen reacts, how many moles of ammonia are produced? If 1 mole of carbon dioxide (CO2) is decomposed into its elements, how many moles of oxygen (O2) are produced? Medium Difficulty Questions: In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), if 4 moles of iron(III) oxide are produced, how many moles of iron were needed? In the synthesis of ammonia (NH3) from nitrogen (N2) and hydrogen (H2), if you want to produce 10 moles of ammonia, how many moles of nitrogen will you need? In the decomposition of water (H2O) into hydrogen (H2) and oxygen (O2), if you start with 18 moles of water, how many moles of oxygen will be produced? Answers Easy Questions: If 2 moles of hydrogen (H2) react with 1 mole of oxygen (O2) to form water (H2O), how many moles of water will be produced?Answer: 2 moles of water will be produced. (Based on the balanced equation: 2H2 + O2 -> 2H2O) In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), if 1 mole of nitrogen reacts, how many moles of ammonia are produced?Answer: 2 moles of ammonia are produced. (Based on the balanced equation: N2 + 3H2 -> 2NH3) If 1 mole of carbon dioxide (CO2) is decomposed into its elements, how many moles of oxygen (O2) are produced?Answer: 1 mole of oxygen is produced. (Based on the balanced equation: CO2 -> C + O2) Medium Difficulty Questions: In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), if 4 moles of iron(III) oxide are produced, how many moles of iron were needed?Answer: 8 moles of iron were needed. (Based on the balanced equation: 4Fe + 3O2 -> 2Fe2O3) In the synthesis of ammonia (NH3) from nitrogen (N2) and hydrogen (H2), if you want to produce 10 moles of ammonia, how many moles of nitrogen will you need?Answer: 5 moles of nitrogen are needed. (Based on the balanced equation: N2 + 3H2 -> 2NH3) In the decomposition of water (H2O) into hydrogen (H2) and oxygen (O2), if you start with 18 moles of water, how many moles of oxygen will be produced?Answer: 9 moles of oxygen are produced. (Based on the balanced equation: 2H2O -> 2H2 + O2) 2. Mass Relations and Mass-to-Mass Ratio: - Write the mass ratio of a given reaction. Easy Questions: In the reaction of hydrogen (H2) with oxygen (O2) to form water (H2O), what is the mass ratio of hydrogen to oxygen? Answer: The mass ratio of hydrogen to oxygen is 2g:32g. In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), what is the mass ratio of nitrogen to hydrogen? Answer: The mass ratio of nitrogen to hydrogen is 28g:6g. In the reaction of carbon (C) with oxygen (O2) to form carbon dioxide (CO2), what is the mass ratio of carbon to oxygen? Answer: The mass ratio of carbon to oxygen is 12g:32g. Medium Difficulty Questions: In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), what is the mass ratio of iron to oxygen? Answer: The mass ratio of iron to oxygen is 112g:96g. In the synthesis of ammonia (NH3) from nitrogen (N2) and hydrogen (H2), what is the mass ratio of nitrogen to hydrogen? Answer: The mass ratio of nitrogen to hydrogen is 28g:6g. In the decomposition of water (H2O) into hydrogen (H2) and oxygen (O2), what is the mass ratio of hydrogen to oxygen? Answer: The mass ratio of hydrogen to oxygen is 2g:32g. - Find the mass of the product formed from a given mass of reactant. Easy Problems: If 4 grams of hydrogen (H2) react with sufficient oxygen (O2) to form water (H2O), what is the mass of water formed? Answer: The molar mass of hydrogen (H2) is 2g/mol and that of water (H2O) is 18g/mol. Therefore, the mass of water formed is (4g H2) * (18g H2O / 2g H2) = 36g of H2O. If 28 grams of nitrogen (N2) react with sufficient hydrogen (H2) to form ammonia (NH3), what is the mass of ammonia formed? Answer: The molar mass of nitrogen (N2) is 28g/mol and that of ammonia (NH3) is 17g/mol. Therefore, the mass of ammonia formed is (28g N2) * (2 * 17g NH3 / 28g N2) = 34g of NH3. If 12 grams of carbon (C) react with sufficient oxygen (O2) to form carbon dioxide (CO2), what is the mass of carbon dioxide formed? Answer: The molar mass of carbon (C) is 12g/mol and that of carbon dioxide (CO2) is 44g/mol. Therefore, the mass of carbon dioxide formed is (12g C) * (44g CO2 / 12g C) = 44g of CO2. Difficult Problems: If 64 grams of sulfur (S8) react with sufficient oxygen (O2) to form sulfur dioxide (SO2), what is the mass of sulfur dioxide formed? Answer: The molar mass of sulfur (S8) is 256g/mol and that of sulfur dioxide (SO2) is 64g/mol. Therefore, the mass of sulfur dioxide formed is (64g S8) * (8 * 64g SO2 / 256g S8) = 128g of SO2. If 56 grams of iron (Fe) react with sufficient oxygen (O2) to form iron(III) oxide (Fe2O3), what is the mass of iron(III) oxide formed? Answer: The molar mass of iron (Fe) is 56g/mol and that of iron(III) oxide (Fe2O3) is 160g/mol. Therefore, the mass of iron(III) oxide formed is (56g Fe) * (160g Fe2O3 / 112g Fe) = 80g of Fe2O3. If 27 grams of aluminum (Al) react with sufficient oxygen (O2) to form aluminum oxide (Al2O3), what is the mass of aluminum oxide formed? Answer: The molar mass of aluminum (Al) is 27g/mol and that of aluminum oxide (Al2O3) is 102g/mol. Therefore, the mass of aluminum oxide formed is (27g Al) * (102g Al2O3 / 54g Al) = 51g of Al2O3. - Find the mass of a given number of moles of a substance. Easy Problems: What is the mass of 2 moles of hydrogen (H2)? Answer: The molar mass of hydrogen (H2) is 2g/mol. Therefore, the mass of 2 moles of hydrogen is (2 moles) * (2g/mol) = 4g. What is the mass of 1 mole of nitrogen (N2)? Answer: The molar mass of nitrogen (N2) is 28g/mol. Therefore, the mass of 1 mole of nitrogen is (1 mole) * (28g/mol) = 28g. What is the mass of 3 moles of carbon (C)? Answer: The molar mass of carbon (C) is 12g/mol. Therefore, the mass of 3 moles of carbon is (3 moles) * (12g/mol) = 36g. Difficult Problems: What is the mass of 0.5 moles of sulfur (S8)? Answer: The molar mass of sulfur (S8) is 256g/mol. Therefore, the mass of 0.5 moles of sulfur is (0.5 moles) * (256g/mol) = 128g. What is the mass of 2.5 moles of iron (Fe)? Answer: The molar mass of iron (Fe) is 56g/mol. Therefore, the mass of 2.5 moles of iron is (2.5 moles) * (56g/mol) = 140g. What is the mass of 1.5 moles of aluminum (Al)? Answer: The molar mass of aluminum (Al) is 27g/mol. Therefore, the mass of 1.5 moles of aluminum is (1.5 moles) * (27g/mol) = 40.5g. 3. Volume Relations and Volume-to-Mole Ratio: - Give the reacting ratios in moles, mass, and volume. Easy Problems: In the reaction of hydrogen (H2) with oxygen (O2) to form water (H2O), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 2:1 in moles (2 moles of H2 react with 1 mole of O2), 2g:32g in mass, and 44.8L:22.4L in volume. In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 1:3 in moles (1 mole of N2 reacts with 3 moles of H2), 28g:6g in mass, and 22.4L:67.2L in volume. In the reaction of carbon (C) with oxygen (O2) to form carbon dioxide (CO2), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 1:1 in moles (1 mole of C reacts with 1 mole of O2), 12g:32g in mass, and 22.4L:22.4L in volume. Difficult Problems: In the reaction of sulfur (S8) with oxygen (O2) to form sulfur dioxide (SO2), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 1:8 in moles (1 mole of S8 reacts with 8 moles of O2), 256g:256g in mass, and 22.4L:179.2L in volume. In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 4:3 in moles (4 moles of Fe react with 3 moles of O2), 224g:96g in mass. Volume ratio is not applicable as iron is a solid. In the reaction of aluminum (Al) with oxygen (O2) to form aluminum oxide (Al2O3), what are the reacting ratios in moles, mass, and volume? Answer: The reacting ratios are 4:3 in moles (4 moles of Al react with 3 moles of O2), 108g:96g in mass. Volume ratio is not applicable as aluminum is a solid. - Find the volume of one reactant needed to react with a given number of moles of another reactant. Easy Problems: In the reaction of hydrogen (H2) with oxygen (O2) to form water (H2O), what volume of hydrogen is needed to react with 1 mole of oxygen at STP? Answer: The volume of 2 moles of hydrogen at STP is 44.8 L. Therefore, to react with 1 mole of oxygen, 44.8 L of hydrogen is needed. In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), what volume of hydrogen is needed to react with 1 mole of nitrogen at STP? Answer: The volume of 3 moles of hydrogen at STP is 67.2 L. Therefore, to react with 1 mole of nitrogen, 67.2 L of hydrogen is needed. In the reaction of carbon (C) with oxygen (O2) to form carbon dioxide (CO2), what volume of oxygen is needed to react with 1 mole of carbon at STP? Answer: The volume of 1 mole of oxygen at STP is 22.4 L. Therefore, to react with 1 mole of carbon, 22.4 L of oxygen is needed. Difficult Problems: In the reaction of sulfur (S8) with oxygen (O2) to form sulfur dioxide (SO2), what volume of oxygen is needed to react with 0.5 moles of sulfur at STP? Answer: The volume of 8 moles of oxygen at STP is 179.2 L. Therefore, to react with 0.5 moles of sulfur, 89.6 L of oxygen is needed. In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), what volume of oxygen is needed to react with 2 moles of iron at STP? Answer: The volume of 1.5 moles of oxygen at STP is 33.6 L. Therefore, to react with 2 moles of iron, 33.6 L of oxygen is needed. In the reaction of aluminum (Al) with oxygen (O2) to form aluminum oxide (Al2O3), what volume of oxygen is needed to react with 2 moles of aluminum at STP? Answer: The volume of 1.5 moles of oxygen at STP is 33.6 L. Therefore, to react with 2 moles of aluminum, 33.6 L of oxygen is needed. finding the amount of heat released when a given mass of product is formed from the molar heat of reaction: Easy Problems: In the combustion of methane (CH4), -890.4 kJ of heat is released per mole of CH4 combusted. How much heat is released when 16 g of CH4 (approximately 1 mole) is combusted? Answer: -890.4 kJ of heat is released when 16 g of CH4 is combusted. In the combustion of hydrogen (H2) to form water (H2O), -285.8 kJ of heat is released per mole of H2 combusted. How much heat is released when 2 g of H2 (approximately 1 mole) is combusted? Answer: -285.8 kJ of heat is released when 2 g of H2 is combusted. In the combustion of carbon (C) to form carbon dioxide (CO2), -393.5 kJ of heat is released per mole of C combusted. How much heat is released when 12 g of C (approximately 1 mole) is combusted? Answer: -393.5 kJ of heat is released when 12 g of C is combusted. Difficult Problems: In the combustion of glucose (C6H12O6), -2803 kJ of heat is released per mole of glucose combusted. How much heat is released when 90 g of glucose is combusted? Answer: The molar mass of glucose is approximately 180 g/mol. Therefore, 90 g is approximately 0.5 moles. So, -1401.5 kJ of heat is released when 90 g of glucose is combusted. In the combustion of ethanol (C2H5OH), -1367 kJ of heat is released per mole of ethanol combusted. How much heat is released when 23 g of ethanol is combusted? Answer: The molar mass of ethanol is approximately 46 g/mol. Therefore, 23 g is approximately 0.5 moles. So, -683.5 kJ of heat is released when 23 g of ethanol is combusted. In the combustion of propane (C3H8), -2220 kJ of heat is released per mole of propane combusted. How much heat is released when 22 g of propane is combusted? Answer: The molar mass of propane is approximately 44 g/mol. Therefore, 22 g is approximately 0.5 moles. So, -1110 kJ of heat is released when 22 g of propane is combusted. problems about predicting excess and limiting reagents: Easy Problems: In the reaction of hydrogen (H2) with oxygen (O2) to form water (H2O), if 4 moles of H2 react with 1 mole of O2, which is the limiting reagent? Answer: Oxygen (O2) is the limiting reagent because the reaction requires 2 moles of H2 for every 1 mole of O2. Therefore, there is an excess of H2. In the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3), if 1 mole of N2 reacts with 2 moles of H2, which is the limiting reagent? Answer: Nitrogen (N2) is the limiting reagent because the reaction requires 3 moles of H2 for every 1 mole of N2. Therefore, there is an excess of H2. In the reaction of carbon (C) with oxygen (O2) to form carbon dioxide (CO2), if 1 mole of C reacts with 1 mole of O2, which is the limiting reagent? Answer: Neither is the limiting reagent because the reaction requires 1 mole of C for every 1 mole of O2. Therefore, there is no excess reagent. Medium Difficulty Problems: In the reaction of sulfur (S8) with oxygen (O2) to form sulfur dioxide (SO2), if 1 mole of S8 reacts with 6 moles of O2, which is the limiting reagent? Answer: Sulfur (S8) is the limiting reagent because the reaction requires 8 moles of O2 for every 1 mole of S8. Therefore, there is an excess of O2. In the reaction of iron (Fe) with oxygen (O2) to form iron(III) oxide (Fe2O3), if 4 moles of Fe react with 2 moles of O2, which is the limiting reagent? Answer: Oxygen (O2) is the limiting reagent because the reaction requires 3 moles of O2 for every 4 moles of Fe. Therefore, there is an excess of Fe. In the reaction of aluminum (Al) with oxygen (O2) to form aluminum oxide (Al2O3), if 4 moles of Al react with 2 moles of O2, which is the limiting reagent? Answer: Aluminum (Al) is the limiting reagent because the reaction requires 3 moles of O2 for every 4 moles of Al. Therefore, there is an excess of O2. Difficult Problems: In the reaction of glucose (C6H12O6) with oxygen (O2) to form carbon dioxide (CO2) and water (H2O), if 1 mole of C6H12O6 reacts with 5 moles of O2, which is the limiting reagent? Answer: Oxygen (O2) is the limiting reagent because the reaction requires 6 moles of O2 for every 1 mole of C6H12O6. Therefore, there is an excess of C6H12O6. In the reaction of ethanol (C2H5OH) with oxygen (O2) to form carbon dioxide (CO2) and water (H2O), if 1 mole of C2H5OH reacts with 2 moles of O2, which is the limiting reagent? Answer: Ethanol (C2H5OH) is the limiting reagent because the reaction requires 3 moles of O2 for every 1 mole of C2H5OH. Therefore, there is an excess of O2. In the reaction of propane (C3H8) with oxygen (O2) to form carbon dioxide (CO2) and water (H2O), if 1 mole of C3H8 reacts with 4 moles of O2, which is the limiting reagent? Answer: Propane (C3H8) is the limiting reagent because the reaction requires 5 moles of O2 for every 1 mole of C3H8. Therefore, there is an excess of O2.

Lesson 37 Structure of the atom and the periodic table Chapter 7 SABIS Grade 10 Part 1 Lesson 37 Structure of the atom and the periodic table Chapter 7 Structure of the atom and the periodic table Lesson 1 Content 7.1 Structure of the Atom 7.1.1 The nuclear atom 7.1.2 What the nucleus contains 7.1.3 Nuclei of atoms of the same element 7.1.4 Neutral atoms and the formation of ions 7.1.5 Mass of subatomic particles 7.1.6 The nuclear model 7.1.7 The sizes of atoms 7.1.8 Atomic number 7.1.9 Mass number Symbols to refer to elements in chemical reactions Symbols to refer to atomic nuclei 7.1.10 Isotopes Pre-Requisite Questions: What are the three main particles that make up an atom? 🧐 Can you recall what an ion is? 💡 What is the significance of the atomic number of an element? 🤔 What do you understand by the term 'isotopes'? 🤨 What's the main difference between a cation and an anion? 🙄 (Answers: 1. Protons, Neutrons, and Electrons. 2. An ion is an atom or molecule with a net electric charge due to the loss or gain of one or more electrons. 3. The atomic number of an element represents the number of protons in its nucleus. 4. Isotopes are variants of the same element with the same number of protons but different numbers of neutrons. 5. Cations are positively charged ions, and anions are negatively charged ions.) 🎯Lesson Begins 📍What's Inside the Atom? Atoms are like the invisible LEGO blocks that make up everything we see and touch. An atom consists of subatomic particles—protons, neutrons, and electrons. 😲 Imagine an atom as a tiny solar system, with a nucleus at the center like the sun and electrons whizzing around like planets. 🌞🪐 🏟️Nuclear Atom The center, or nucleus, of the atom is where we find the protons and neutrons. Protons carry a positive charge (like the positive vibe in a party 🥳), and neutrons have no charge—they're the cool, neutral folks at the party. ⚖️ 📏Size of an Atom Atoms are incredibly tiny. The diameter of an atom—the distance between two adjacent nuclei—is in the order of 10^-10 meters. 📏That's about a hundred million times smaller than an apple seed! 🍎 The diameter of the nucleus is even tinier, at about 10^-14 meters. Picture a pea in the middle of a football stadium—that's how empty an atom is! 🏈🏟️ ⚖️Mass of an Atom The protons and neutrons together are known as nucleons. They're the heavyweight champs of the atom, with most of the mass concentrated in the nucleus. 🏋️♂️ On the other hand, electrons are featherweights, weighing about 1/1840 the mass of a proton. 🔋Charge of an Atom An atom, like your favorite superhero, is electrically neutral—meaning it has an equal number of positive protons and negative electrons, balancing each other out. 💪 🔄Formation of Ions Ions are formed when atoms lose or gain electrons. Losing an electron forms a cation (a positively charged ion), kind of like losing weight and becoming positively happier! 🤸♂️🎈 Conversely, gaining an electron forms an anion (a negatively charged ion), like gaining responsibilities and getting negatively stressed! 😓📚 🔢Atomic Number and Mass Number Think of the atomic number (Z) as the ID card of an element—it tells us the number of protons in an atom. In a neutral atom, it also equals the number of electrons. The mass number (A), on the other hand, is like the total weight of an atom—it adds up the number of protons (P) and neutrons (N) in an atom. Simple math, right? 1️⃣2️⃣3️⃣ 🎭Isotopes Isotopes are like the twins of an element. They have the same atomic number, but a different mass number. For example, hydrogen (1H), deuterium (2H), and tritium (3H) are all isotopes of hydrogen—they all have 1 proton, but a different number of neutrons (0, 1, and 2 respectively). It's like different flavors of your favorite ice cream—different tastes, but still ice cream! 🍨 Review Questions: What is the order of the diameter of an atom? a. 10^-10 m b. 10^-14 m c. 10^10 m d. 10^14 m What do we call an atom that has gained or lost electrons? a. Isotope b. Ion c. Cation d. Neutron Which particle is found inside the nucleus of an atom? a. Protons b. Neutrons c. Electrons d. Both a and b Which of these is the best definition of isotopes? a. Atoms of the same element with the same number of protons but different numbers of neutrons. b. Atoms with the same number of protons but different number of electrons. c. Atoms with the same number of neutrons but different number of protons. d. None of the above An atom that has more protons than electrons is called? a. A cation b. An anion c. A neutron d. An electron (Answers: 1. a, 2. b, 3. d, 4. a, 5. a) Quiz Click on the below and join the quiz if for any reason you can not join the quiz download as pdf and submit after answering and scanning https://quizizz.com/join?gc=72015277 if for any reason you can not join the quiz download here as pdf and submit after answering and scanning K-Chemistry com Chapter 7 Grade 10 SABIS Quiz 20 .pdf Download PDF • 101KB