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Effect of changing pressure on rate of reaction: Grade 10 SABIS if one or more of the reactants are gaseous, an increase in pressure will increase their concentration. Increasing the concentration, increases the number of particles in a given volume thus the reacting particles will collide more frequently so the number of collisions will increase per unit time, thus rate of reaction increases. Pressure can be increased by either injecting more gas or by decreasing the volume of vessel in which the reaction is occurring.

Reaction of Alkali metals with hydrogen. Grade 10 SABIS Generally: 2M(s) + 2H2(g) → 2MH(s) alkali metal + hydrogen → alkali metal hydride

< Back Chapter 9 Prerequisite Previous Next 🌟📘 Prerequisites for Chapter 9: Rate of Reaction 📘🌟Before diving into Chapter 9, which deals with the rate of reaction, students must have a solid understanding of the following concepts:🔬 1. Basic Chemistry Concepts 🧪Understand atoms, molecules, ions, and chemical reactions.🔬 2. Collision Theory 💥Understand that reactions occur when particles collide with sufficient energy and proper orientation.🔬 3. Activation Energy 🚀Understand the concept of activation energy as the minimum energy required for a reaction to occur.🔬 4. Factors Affecting Reaction Rates 📈Understand how temperature, concentration, surface area, and catalysts affect reaction rates.🌟 20 Multiple Choice Questions for Chapter 9: Rate of Reaction 🌟What is the term for how fast reactants are consumed or products are formed in a chemical reaction? a) Reaction rate b) Activation energy c) Equilibrium constant d) EnthalpyAccording to collision theory, what must occur for a reaction to take place? a) Particles must collide with sufficient energy and proper orientation. b) Particles must collide with low energy. c) Particles must avoid colliding. d) Particles must collide with any orientation.What is the term for the minimum energy that reacting particles must have to form the activated complex? a) Reaction rate b) Activation energy c) Equilibrium constant d) EnthalpyHow does increasing the temperature affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.How does increasing the concentration of reactants affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for a substance that increases the rate of a reaction without being consumed? a) Inhibitor b) Catalyst c) Solvent d) ReactantHow does increasing the surface area of a solid reactant affect the rate of a chemical reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for the highest point on the reaction path where bonds are breaking and new bonds are forming? a) Activated complex b) Transition state c) Reaction intermediate d) Both a and bHow does adding a catalyst affect the activation energy of a reaction? a) Increases activation energy. b) Decreases activation energy. c) Does not affect activation energy. d) Destroys activation energy.What is the effect of a catalyst on the rate of a reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.In the rate expression rate = k[A][B], what does k represent? a) Rate of reaction b) Activation energy c) Rate constant d) Concentration of reactantsHow does increasing the pressure affect the rate of a reaction involving gases? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.What is the term for a graph that shows the change in concentration of reactants or products over time? a) Reaction coordinate diagram b) Reaction rate graph c) Concentration-time graph d) Activation energy graphWhat is the term for a short-lived, high-energy arrangement of atoms during a chemical reaction? a) Activated complex b) Transition state c) Reaction intermediate d) CatalystHow does the presence of a catalyst affect the position of equilibrium in a reaction? a) Shifts it to the right. b) Shifts it to the left. c) Does not change the position. d) Destroys the equilibrium.What is the term for the number of collisions per second between the reactant molecules? a) Collision frequency b) Reaction rate c) Activation energy d) Rate constantWhat is the effect of an inhibitor on the rate of a reaction? a) Increases the rate. b) Decreases the rate. c) Does not affect the rate. d) May increase or decrease the rate.In the reaction A -> B, if the concentration of A decreases linearly over time, what is the order of the reaction? a) Zero order b) First order c) Second order d) Third orderWhat is the term for a substance that slows down the rate of a chemical reaction? a) Inhibitor b) Catalyst c) Solvent d) ReactantIn a first-order reaction, how does the rate of reaction depend on the concentration of the reactant? a) Rate is proportional to the square of the concentration. b) Rate is inversely proportional to the concentration. c) Rate is proportional to the concentration. d) Rate is independent of the concentration.🌟 Answers 🌟a) Reaction ratea) Particles must collide with sufficient energy and proper orientation.b) Activation energya) Increases the rate.a) Increases the rate.b) Catalysta) Increases the rate.d) Both a and bb) Decreases activation energy.a) Increases the rate.c) Rate constanta) Increases the rate.c) Concentration-time grapha) Activated complexc) Does not change the position.a) Collision frequencyb) Decreases the rate.b) First ordera) Inhibitorc) Rate is proportional to the concentration.

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7. The decomposition of water into H2 and O2 gas. Endothermic Grade 10 SABIS SABIS

Enthalpy Change (ΔH) Grade 10 SABIS Enthalpy change, represented as ΔH, is a concept in thermochemistry that describes the difference in heat content between the products and reactants of a chemical reaction. Think of it as the "energy difference" before and after a reaction occurs. Imagine you have a candle burning. The wax and oxygen react to produce carbon dioxide and water vapor. The enthalpy change, ΔH, represents the energy released or absorbed during this combustion process. Now, consider making a cup of tea. When you add hot water to a tea bag, the enthalpy change represents the heat energy transferred to the water, causing it to dissolve the tea compounds and produce a flavorful beverage. In everyday life, we experience enthalpy changes when cooking. For example, when you bake a cake, the enthalpy change occurs as the batter transforms into a delicious, fluffy dessert due to the energy released during the chemical reactions between the ingredients. Similarly, when you boil water on the stovetop, the enthalpy change indicates the energy absorbed by the water molecules, causing them to gain heat and eventually reach the boiling point. Enthalpy change is crucial for understanding the heat effects in chemical reactions. For instance, in hand warmers, the chemical reaction inside generates an enthalpy change, releasing heat and providing warmth on cold days. In summary, enthalpy change (ΔH) represents the energy difference before and after a chemical reaction. It influences everyday scenarios like cooking, brewing tea, and even hand warmers. By studying enthalpy changes, we can comprehend the heat transfers and energy transformations that occur in various processes around us.

Sodium chloride is a very stable compound because Na+ ion has 10 electrons around it (like noble gas before it, Ne) and the Cl- has 18 electrons around it (like noble gas after it. Ar). Grade 10 SABIS

Energy Conversion Grade 10 SABIS Energy conversion refers to the process of transforming energy from one form to another. It involves the conversion of energy between different types, such as mechanical, electrical, thermal, chemical, or radiant energy. To understand energy conversion, let's consider an everyday example: a car. When you drive a car, the engine converts the chemical energy stored in fuel into mechanical energy to move the vehicle. Here, energy is transformed from the chemical form (fuel) to mechanical energy (motion). Another example of energy conversion is the use of solar panels to generate electricity. Solar panels convert radiant energy from the sun into electrical energy, which can be used to power homes, devices, or charge batteries. In a similar manner, a wind turbine converts the kinetic energy of the wind into electrical energy. The movement of the wind blades causes the rotor to spin, generating electricity through the conversion of kinetic energy to electrical energy. In thermodynamics, a steam power plant exemplifies energy conversion. Heat energy from burning fossil fuels or nuclear reactions is used to produce steam, which then drives a turbine to generate electrical energy. Here, the energy is converted from thermal energy to mechanical energy and finally to electrical energy. Energy conversion is also evident in the use of batteries. When you charge a battery, electrical energy from a power source is converted into chemical energy, which is stored in the battery for later use. When you use the battery, the stored chemical energy is then converted back into electrical energy. Furthermore, when you switch on a light bulb, electrical energy is converted into radiant energy (light) and thermal energy (heat) as the filament emits light and produces heat. In our bodies, food is converted into energy through a process called cellular respiration. The chemical energy stored in food molecules is transformed into usable energy in the form of adenosine triphosphate (ATP), which powers various biological processes. Energy conversion is essential in various industries and technologies. For example, in hydroelectric power plants, the potential energy of water stored in dams is converted into kinetic energy as it flows downhill, which is then transformed into electrical energy. In summary, energy conversion is the process of transforming energy from one form to another. Examples such as cars converting chemical energy to mechanical energy, solar panels converting radiant energy to electrical energy, and batteries converting electrical energy to chemical energy help illustrate the concept. Energy conversion plays a crucial role in various systems, technologies, and natural processes, enabling the utilization and transfer of energy in different forms for everyday applications.

Conservation of Mass Grade 10 SABIS SABIS In chemical reactions, the total mass of the reactants is equal to the total mass of the products. This principle states that matter cannot be created or destroyed.

< Back Atomic Structure Lesson 5 ⚛️ Lesson 5 ⚛️ Discover the secrets of isotopes in this visually enhanced content. Learn about their similarities and differences, how to identify them, and their impact on chemical and physical properties. Build on your understanding of atomic structure to explore the intriguing world of isotopes and unlock new dimensions of exploration and discovery. Previous Next ⚛️1.1.5 Isotopes⚛️ ✨🔬 Unveiling the Secrets of Isotopes: Similar Yet Different 🔬✨ 🌟 The Isotope Dance: Same Protons, Different Neutrons 🌟 Isotopes are like siblings within the atomic family—they share the same number of protons and electrons but have a unique twist: a different number of neutrons. 🧑🔬⚛️ To identify an isotope, we use the chemical symbol (or word) of the element, followed by a dash and the mass number. For example, carbon-12 and carbon-14 are isotopes of carbon with 6 and 8 neutrons, respectively. 🎭 💥 Chemical Properties: A Common Chemistry 💥 When it comes to chemical properties, isotopes of the same element exhibit strikingly similar behaviors. Why? It's all about the electrons! The number of electrons in their outer shells determines an atom's chemistry, and isotopes share the same number of electrons in their respective elements. 🌌🔍 Whether it's carbon-12 or carbon-14, their outer electron shells hold the same number of electrons. Thus, they participate in chemical reactions in the same way, showcasing identical chemical characteristics. 🌟⚗️ 🌈 Physical Properties: Nuanced Differences 🌈 While isotopes share similar chemical behavior, their physical properties present subtle distinctions. The key variance lies in the number of neutrons. Neutrons are neutral subatomic particles that contribute to an atom's mass without affecting its charge. 💪 Due to these additional neutrons, isotopes exhibit slight differences in physical properties such as mass and density. These disparities, though small, are the fingerprints that set isotopes apart, enabling us to distinguish them and study their unique characteristics. ✋📊 🧠 Prerequisite: Atomic Structure 🧠 To grasp the concept of isotopes fully, understanding the fundamentals of atomic structure is crucial. This includes knowledge of protons, neutrons, and electrons, their charges, and their roles within the atom. With this foundation, we can explore the fascinating world of isotopes and their properties. 🌌💡 So, as we unveil the secrets of isotopes, remember that while they may appear similar in the world of chemistry, their underlying differences open up a whole new dimension of exploration and discovery! 🌟🚀

The burning of a magnesium ribbon in air Grade 10 SABIS SABIS Exothermic