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54b02bf5-d064-4530-aa18-ece42beb78d7 Know the meaning of the term “calorimetry” in SABIS Summary It is the measurement of reaction heats

6db8ab25-5121-4066-aa23-2ee26c0e25fa Reading Equations Summary Using masses of reactants and products

< Back Unit 1 AP Chemistry Topic 5 Periodic Trends You can get more out of your site elements by making them dynamic. To connect this element to content from your collection, select the element and click Connect to Data. Once connected, you can save time by updating your content straight from your collection—no need to open the Editor, or mess with your design. Add any type of content to your collection, such as rich text, images, videos and more, or upload a CSV file. You can also collect and store information from your site visitors using input elements like custom forms and fields. Collaborate on your content across teams by assigning permissions setting custom permissions for every collection. Be sure to click Sync after making changes in a collection, so visitors can see your newest content on your live site. Preview your site to check that all your elements are displaying content from the right collection fields. Ready to publish? Simply click Publish in the top right of the Editor and your changes will appear live. Unit 1 Topic 5 Periodic Trends Previous Next

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

< Back Hydroxy compounds Previous Next

Chapter 4 SABIS Grade 10 Part 7 Lesson 22: Limiting Reagents and Excess Reagents 🧪🥽🔍 In chemistry, reactions 🔄 don't always use up all the reactants equally. Sometimes, one reactant gets used up first. That reactant is called the Limiting Reagent because its amount limits the amount of product that can be formed. The reactant that is not completely used up is called the Excess Reagent . Let's get a grasp on this concept with a few basic questions 🤔: Basic Question 7: Limiting and Excess Reagents Consider the following balanced chemical equation: 4Fe + 3O2 → 2Fe2O3 If you started the reaction with 5 moles of Fe and 4 moles of O2, which one is the limiting reagent? Which one is in excess? How many moles of Fe2O3 can be formed? How many moles of the excess reagent will be left over at the end of the reaction? Given: 5 moles Fe and 4 moles O2 For Fe: 5 moles Fe x (2 moles Fe2O3 / 4 moles Fe) = 2.5 moles Fe2O3 For O2: 4 moles O2 x (2 moles Fe2O3 / 3 moles O2) = 2.67 moles Fe2O3 The smaller value will determine the amount of product formed and hence Fe is the limiting reagent here. Using up 5 moles of Fe will consume 3.75 moles of O2 (from 5 moles Fe x 3 moles O2 / 4 moles Fe), leaving 0.25 moles of O2 unused, so O2 is the excess reagent. We can form 2.5 moles of Fe2O3 based on the amount of the limiting reagent. Let's try another example to strengthen our understanding of this concept: Additional Example Consider the following balanced chemical equation: 2H2 + O2 → 2H2O If you started the reaction with 5 moles of H2 and 3 moles of O2, which one is the limiting reagent? Which one is in excess? How many moles of H2O can be formed? How many moles of the excess reagent will be left over at the end of the reaction? Given: 5 moles H2 and 3 moles O2 For H2: 5 moles H2 x (2 moles H2O / 2 moles H2) = 5 moles H2O For O2: 3 moles O2 x (2 moles H2O / 1 mole O2) = 6 moles H2O The smaller value will determine the amount of product formed and hence H2 is the limiting reagent here. Using up 5 moles of H2 will consume 2.5 moles of O2 (from 5 moles H2 x 1 mole O2 / 2 moles H2), leaving 0.5 moles of O2 unused, so O2 is the excess reagent. We can form 5 moles of H2O based on the amount of the limiting reagent. Great work! You've got this! 💪😁

a69fa2f3-d52c-4396-a240-70da69e3b9f2 Electrochemistry Electrochemical cell interactive link here. https://examprepnotes.com/electrochemical-cells Summary

SABIS Grade 12 T1 W2 2526 } body

< Back Nitrogen and sulfur Previous Next 🔬 Chapter 13: Nitrogen and Sulfur 🔬 Learning Outcomes 🎯: Describe and explain the lack of reactivity of nitrogen gas, the basicity of ammonia, and the formation and structure of the ammonium ion. State the industrial importance of ammonia and nitrogen compounds derived from ammonia. State and explain the environmental consequences of the uncontrolled use of nitrate fertilizers. Describe the natural and man-made occurrences of oxides of nitrogen and their catalytic removal from exhaust gases of internal combustion engines. Describe the formation of sulfur dioxide gas from sulfur-contaminated fossil fuel, its role in the formation of acid rain, and how acid rain affects the environment. Nitrogen and Its Compounds 🌬️: Nitrogen gas is relatively unreactive due to the triple bond between nitrogen atoms in N2 molecules. Ammonia is a basic compound that forms the ammonium ion when it reacts with acids. Ammonia and its derivatives are industrially important, especially in the production of fertilizers. Environmental Impact of Nitrogen Compounds 🌍: The excessive use of nitrate fertilizers can lead to environmental problems such as water pollution and eutrophication. Oxides of nitrogen are pollutants that can be produced naturally or by human activities, such as combustion in engines. They play a role in the formation of acid rain. Sulfur Dioxide and Acid Rain ☔: Sulfur dioxide is produced when sulfur-containing fossil fuels are burned. It is a major contributor to acid rain, which can have harmful effects on the environment, including soil, water, and buildings.

42c6640c-1f62-4004-ae4c-509dd4ad470e Microscopic changes that take place when a liquid is warmed Summary When a liquid is warmed in thermochemistry, several microscopic changes occur at the molecular level. These changes involve the increased kinetic energy of the liquid molecules and their interactions, leading to observable macroscopic effects such as expansion and changes in physical properties. As the liquid is heated, the temperature of the system rises, and this increase in temperature corresponds to an increase in the average kinetic energy of the liquid molecules. The molecules gain energy and move more rapidly, exhibiting increased vibrational, rotational, and translational motion. The increased kinetic energy causes the intermolecular forces between the liquid molecules to weaken. In the liquid state, these forces, such as hydrogen bonding or London dispersion forces, hold the molecules together in a cohesive arrangement. As the molecules gain energy, the forces become less effective at maintaining this cohesion. The weakened intermolecular forces result in an expansion of the liquid. The increased molecular motion and reduced intermolecular forces allow the molecules to move farther apart, leading to an increase in volume. This expansion is commonly observed in liquids when they are heated. Additionally, the increased kinetic energy can lead to changes in the physical properties of the liquid. For example, the viscosity of the liquid may decrease as the molecules move more freely and with less resistance. The surface tension may also decrease as the cohesive forces weaken, affecting the behavior of the liquid at interfaces. Furthermore, in some cases, when a liquid is heated sufficiently, it may undergo a phase change and transform into a gas. This transition occurs at the boiling point, where the vapor pressure of the liquid becomes equal to the external pressure. The heated liquid absorbs energy to overcome intermolecular forces and transition into a gas phase. It's important to note that the microscopic changes in a liquid being warmed are reversible. When the liquid is cooled, the molecules lose kinetic energy, and the intermolecular forces regain their effectiveness, leading to a decrease in volume and a return to the initial state. Understanding the microscopic changes that occur when a liquid is warmed is crucial in thermochemistry and various applications. It allows us to analyze energy transfers, phase transitions, and the behavior of substances under different temperature conditions. In summary, when a liquid is warmed in thermochemistry, microscopic changes take place at the molecular level. The increased kinetic energy of the molecules weakens the intermolecular forces, resulting in expansion, changes in physical properties, and, in some cases, phase transitions. Recognizing and studying these microscopic changes enhances our understanding of energy transfer and the behavior of liquids at different temperatures.

3368b554-6764-42d8-8f1e-81bb53feca19 Volume at STP Summary 1.00 mole of ANY gas occupies 22.4 dm3

A level Cambridge Chemistry Atomic Structure Lesson 1 ⚛️ Lesson 1 ⚛️ Read More Atomic Structure Lesson 2 ⚛️ Lesson 2 ⚛️ Read More Atomic Structure Lesson 3 ⚛️ Lesson 3 ⚛️ Read More Atomic Structure Lesson 4 ⚛️ Lesson 4 ⚛️ Read More Atomic Structure Lesson 5 ⚛️ Lesson 5 ⚛️ Read More Atomic Structure Lesson 6 ⚛️ Lesson 6 ⚛️ Read More Atomic Structure Lesson 7 ⚛️ Lesson 7 ⚛️ Read More Read More ⚛️ Lesson 8 ⚛️ Read More ⚛️ Lesson 9 ⚛️ Read More ⚛️ Lesson 10 ⚛️ Read More ⚛️ Lesson 11 ⚛️ Read More ⚛️ Lesson 12 ⚛️ Read More ⚛️ Lesson 13 ⚛️ Read More ⚛️ Lesson 14 ⚛️ Read More Atoms, molecules and stoichiometry This is placeholder text. To change this content, double-click on the element and click Change Content. Read More Chemical bonding This is placeholder text. To change this content, double-click on the element and click Change Content. Read More Chemical Bonding prerequisite Read More States of matter Read More Prerequisites for Chapter 5: States of Matter Read More Chemical energetics Exploring the Energetic World of Chemical Reactions and Thermodynamics Read More Chemical Thermodynamics Prerequisites Read More Electrochemistry Read More Chapter 7 Pre requisite Read More Equilibria Read More Chapter 8 Prerequisite Read More Reaction kinetics Read More Chapter 9 Prerequisite Read More The Periodic Table: chemical periodicity Read More Chapter 10 prerequisite Read More Group 2 Read More Chapter 11 Prerequisite Read More Group 17 Read More Chapter 12 prerequisite Read More Nitrogen and sulfur Read More Chapter 13 prerequisite Read More Hydrocarbons Read More Organic chemistry Read More Halogen compounds Read More Hydroxy compounds Read More