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2a5b4fd0-795d-4617-9376-ae7d3f10b834 Mixtures Separation Techniques 2 Distillation chromatography Summary

84538d54-72de-42cb-a15a-aa0011829040 Group 1 metals (alkali metals): each has 1 more electron than the noble gas before it  they form stable 1+ ions which have a noble gas electron arrangement. Summary

68bbcb57-fcf9-4062-a7be-e638a8269157 Kinetic Energy Summary Kinetic energy is the energy an object possesses due to its motion. It is dependent on the mass and velocity of the object and is one of the fundamental forms of energy. To understand kinetic energy, let's consider an everyday example: a moving car. When a car is in motion, it possesses kinetic energy. The faster the car moves and the more massive it is, the greater its kinetic energy. Similarly, when you kick a soccer ball, the ball gains kinetic energy as it moves through the air. The speed and mass of the ball determine the amount of kinetic energy it possesses. Another example is a swinging pendulum. As the pendulum swings back and forth, it alternates between potential energy at the highest point and kinetic energy at the lowest point. The greater the amplitude and speed of the swing, the higher the kinetic energy. In sports, the energy of a moving basketball player illustrates kinetic energy. When a basketball player dribbles the ball and runs across the court, both the player and the ball possess kinetic energy due to their motion. Moving water in a river or a waterfall also possesses kinetic energy. The faster the water flows and the larger its volume, the greater its kinetic energy. This kinetic energy can be harnessed and converted into electrical energy in hydroelectric power plants. When you ride a bicycle, the kinetic energy of your body and the bicycle is determined by your speed and mass. The faster you pedal and the more massive the bicycle and rider, the greater the kinetic energy. In roller coasters, kinetic energy plays a significant role. As the coaster cars descend from a high point, their potential energy is converted into kinetic energy, resulting in thrilling speeds and sensations. In a car crash, the concept of kinetic energy is crucial. The energy of a moving car transforms into destructive force upon impact. This emphasizes the importance of safety measures and the need to minimize kinetic energy in collisions. In summary, kinetic energy is the energy of an object due to its motion. Examples like moving cars, swinging pendulums, basketball players, flowing water, bicycles, roller coasters, and car crashes help illustrate the concept of kinetic energy. Understanding kinetic energy is essential in various fields, from sports to engineering, as it allows us to quantify and comprehend the energy associated with moving objects and their interactions.

Chapter 5 SABIS Grade 10 Lesson 4 Lesson 28 Part 4: Going Deeper into Gas Laws 😮💨📚⚗️ Concept 1: The Intricacies of Partial Pressure and Mole Fractions ⚖️💨 🔮 Partial Pressure (P): Imagine you have a party 🥳🎈 where everyone is talking at the same time. The noise level each person contributes is the "Partial Noise" they're making. Similarly, in a gas mixture, the pressure that each gas would exert if it were alone in the vessel is called its Partial Pressure! 🌈 Mole Fraction (X): The mole fraction of a gas is like a gas's share 🍰 of the total number of moles in the mix. It's calculated as the number of moles of that specific gas (n1) divided by the total number of moles (nT). Mole fractions are cool because their sum always equals one, just like fractions of a pie must add up to make the whole pie! 🥧 Quick Quiz 🤓🎯 What is the Partial Pressure of a gas? A) The total pressure of the gas mixture. B) The pressure a gas would exert if it alone were in the vessel. C) The pressure exerted by the walls of the vessel. D) The pressure when the temperature is constant. Answer: B) The pressure a gas would exert if it alone were in the vessel. What is the Mole Fraction of a gas? A) The total number of moles in the mixture. B) The number of moles of a specific gas in the mixture. C) The ratio of the number of moles of a specific gas to the total number of moles. D) The number of moles of a gas in one mole of the mixture. Answer: C) The ratio of the number of moles of a specific gas to the total number of moles. Concept 2: Real Gases versus Ideal Gases 🌫️🌐 Who behaves better? 😇👹 In a perfect world, all gases would be ideal gases. They would follow the ideal gas law, PV=nRT, with no exceptions 🌈. But just like people, gases aren't perfect, and we call them real gases. They differ from ideal gases because their particles occupy volume and exert forces on each other. Real gases also deviate more from ideal behavior at high pressures and low temperatures, and can even liquefy under these conditions! 😮 Quick Quiz 🤓🎯 How do real gases differ from ideal gases? A) Their particles occupy volume and exert forces on each other. B) They deviate more from ideal behavior at high pressures and low temperatures. C) They can liquefy at high pressures and low temperatures. D) All of the above Answer: D) All of the above Concept 3: Unpacking Gas Laws - Charles’ Law, Pressure-Temperature Behavior and Boyle’s Law 📘🔬 These laws help us understand how gases behave under different conditions. Charles’ Law 🎈: Charles' Law says that, for a fixed amount of gas at a constant pressure, the volume is directly proportional to the absolute temperature (K). That means if you heat a balloon, it'll expand 🎈🔥! Pressure-Temperature Behavior 😤💥: Just like you might get agitated in the heat, gas particles move faster and collide more often when the temperature rises, increasing the pressure. Boyle’s Law 🥫: Boyle's Law states that the pressure of a fixed amount of gas is inversely proportional to its volume at a constant temperature. Think of it like this: try to squeeze a balloon 🎈. The smaller it gets, the harder you have to squeeze. The same happens with gas: as the volume decreases, the pressure increases. Quick Quiz 🤓🎯 What happens to the volume of a gas if you heat it while keeping the pressure constant (according to Charles' Law)? A) The volume decreases. B) The volume stays the same. C) The volume increases. D) The volume fluctuates randomly. Answer: C) The volume increases. What happens to the pressure of a gas when you increase the temperature? A) The pressure decreases. B) The pressure stays the same. C) The pressure increases. D) The pressure becomes zero. Answer: C) The pressure increases. How is pressure related to volume in Boyle's Law? A) They are directly proportional. B) They are inversely proportional. C) They are not related. D) The relation depends on the temperature. Answer: B) They are inversely proportional. Concept 4: The Equation of State & Ideal Gas Law 📚💡 Decoding the Equation of State 🗝️🧮 The equation of state, also known as the ideal gas law (PV = nRT), describes how gases behave. Each symbol represents: P: Pressure in atm V: Volume in dm³ or L n: Number of moles of gas T: Absolute temperature in Kelvin (T = t°C + 273) R: Universal gas constant, 0.0821 atm . dm³.K⁻¹.mole⁻¹ There's also a modified form of the equation, PM = dRT, where d is the density (g/dm³) and M is the molar mass (g/mole) of the gas. Let's visualize this! Imagine a balloon 🎈: the pressure inside (P) is like kids pushing against the balloon walls to make it expand. The volume (V) is how much space the balloon takes up. The number of moles (n) represents how many kids are inside the balloon. The absolute temperature (T) is like the energy level of the kids - the higher the energy, the more they push and move. Quick Quiz 🤓🎯 What does 'P' represent in the ideal gas law (PV = nRT)? A) Volume B) Number of moles C) Pressure D) Temperature Answer: C) Pressure Concept 5: Summary of Relations for Ideal Gases 🌬️📝 The Beauty of Relationships Ideal gases have specific relations between their properties (pressure, volume, moles, and temperature). For example, if we keep the number of moles (n) and temperature (T) constant, the pressure (P) of a gas is inversely proportional to its volume (V). This is simply Boyle's law, P1V1=P2V2! There are many other relations, and you can see them as mathematical expressions and visualize them in graphs! 📈📉📊 Concept 6: Applications 🎯💼 Now, you might wonder, "Where will I use this in real life?" Well, gas laws apply in various fields! 🏥 In medicine, they're used to determine the correct mixture of gases for anesthesia. 🚀 In space science, they're essential to understand the atmospheres of other planets. 🎈🔥 And in everyday life, they explain why hot air balloons rise and why opened soda goes flat. Now, let's move on to the quiz! 💪 Final Quiz: Final Test Time: Ready to Show Your Gas Laws Mastery? 🎓🔥 Question 1: 🚗💨 You're on a road trip with your family. Your dad is driving, and you notice that the car tire is slightly flat. He says he'll inflate it when you guys stop for lunch because it's really hot right now. Why does he wait? A) Heat makes the pump work less efficiently B) The hot weather will automatically inflate the tire C) Hot air inside the tire will exert more pressure D) None of the above Question 2: 🏀🥶 If you leave a basketball in a cold room, it gets a bit deflated. Why is that? A) The basketball material shrinks in cold temperatures B) The gas particles inside the basketball slow down and take up less space C) The basketball ghosts are just playing a prank D) The cold makes the air leak out from the basketball Question 3: 🚀 When launching a rocket into space, scientists have to consider the gas laws. Why is that? A) They love the look of the gas law formulas B) The changing atmospheric pressure affects the rocket’s fuel C) They need something to keep them busy D) Gases make the rocket look cooler Question 4: 🍹 When you open a can of soda, why does it fizz? A) The soda is scared of coming out B) The change in pressure allows the dissolved CO2 to escape C) The soda wants to celebrate its freedom D) The can is mad at you for opening it Question 5: 🎈 You blow up a balloon and let it go. Instead of popping, it flies around the room. What gas law is this showing? A) Charles' Law B) Boyle’s Law C) Graham’s Law D) Dalton’s Law Question 6: 😴💤 You fall asleep while studying for your chemistry exam (oops!) and your head rests on your textbook, drooling on the page about the ideal gas law. When you wake up, all that remains legible is "V = ___ * T". Fill in the blank! A) nR/P B) P/nR C) nRT/P D) RT/Pn Question 7: ⚾️💥 You’re playing baseball, and the ball hits a bottle of perfume in your mom’s room. Whoops! Now the whole house smells like that perfume. Which gas law is at work here? A) Graham’s Law of Effusion B) Boyle’s Law C) Charles’ Law D) Mom’s Law of Grounding Question 8: 🌡️ You're on a camping trip and notice that the campfire isn't just making the marshmallows roast - the sealed bag of chips is puffing up too. What's happening here? A) The chips are trying to escape the heat B) Heat is causing the air inside the bag to expand C) The chips are allergic to marshmallows D) The fire is making the chips grow Question 9: 💡 What does the 'R' stand for in the Ideal Gas Law equation PV = nRT? A) Radical B) Reaction C) Universal Gas Constant D) Rate Question 10: 🌊 A deep-sea diver must be aware of the gas laws. Why? A) Fish might ask about them B) The pressure changes significantly with depth, affecting the gases in the diver’s body C) The deep sea is a great place to do science homework D) Gas laws help in communicating with marine life Remember, to pass this quiz you need to score at least 70%, that means you need to get at least 7 questions right! No cheating - answer with confidence and may the gas laws be with you! 😎🔥💫 I'll post the answers in just a moment. Take a deep breath (think about all those gas particles you're inhaling and exhaling 😉), and when you're ready, scroll down to check your answers! 📜🔍💯 Quiz Time Answers - Let's Check Your Gas Laws Genius Level! 🧐🎓🌟 Question 1: The correct answer is C) Hot air inside the tire will exert more pressure. Remember, when gas particles heat up, they move faster and collide more frequently with the container walls - which in this case is the tire! Question 2: The correct answer is B) The gas particles inside the basketball slow down and take up less space. Cool, right? When it's cold, the particles lose energy, don't move around as much, and hence, exert less pressure. Question 3: The correct answer is B) The changing atmospheric pressure affects the rocket’s fuel. As the rocket ascends, atmospheric pressure decreases, which impacts how the fuel behaves! Question 4: The correct answer is B) The change in pressure allows the dissolved CO2 to escape. You just unleashed a bunch of fizzy freedom fighters! Question 5: The correct answer is D) Dalton’s Law. When you let the balloon go, the gas inside is pushed out, exerting a force that propels the balloon forward. 🎈➡️💨 Question 6: The correct answer is A) nR/P. If you drooled on the n, R, and P, you should still remember that those variables didn't change their spots in the equation! Question 7: The correct answer is A) Graham’s Law of Effusion. The perfume molecules are small and light, so they quickly spread out through the room. Question 8: The correct answer is B) Heat is causing the air inside the bag to expand. It's not just the marshmallows getting roasted, the air in the chip bag is feeling the heat too! Question 9: The correct answer is C) Universal Gas Constant. R is for the universal gas constant. No, it's not for Radical, as radical as that might have been! Question 10: The correct answer is B) The pressure changes significantly with depth, affecting the gases in the diver’s body. Trust me, understanding the gas laws is far more useful underwater than talking to fish. 😉🐟 So, how did you do? Remember, the goal was to get at least 7 out of 10 right. Did you hit the 70% mark? 🎯💯 If so, great job, you're officially a gas laws guru! If not, no worries – you can always review and try again. Remember, science is all about trial, error, and perseverance! 💪🔬💥 Go to The last part part 5

7c4940f5-dbcc-4302-93aa-68d154e137b6 Mathematical Representation Summary P1V1 = P2V2, which signifies that the product of initial pressure and volume equals the product of final pressure and volume.

How fast the gas diffuses depends on two factors 1 The mass of the particles The rate of diffusion of gases Gases diffuse because the particles collide with other particles, and bounce off in all directions . if you do not know what exactly diffusion means click here first Note that gases do not all diffuse at the same rate. The speed with which the gases diffuse depends on these two factors: 1 The mass of the particles The particles in hydrogen chloride gas are twice as heavy as those in ammonia gas. Cotton wool soaked in ammonia solution is put into one end of a long tube (at A below). It gives off ammonia gas.  At the same time, cotton wool soaked in hydrochloric acid is put into the other end of the tube (at B). It gives off hydrogen chloride gas.  The gases diffuse along the tube. White smoke forms where they meet: The white smoke forms closer to B. So the ammonia particles have travelled further than the hydrogen chloride particles – which means they have travelled faster. The lower the mass of its particles, the faster a gas will diffuse. When particles collide and bounce away, the lighter particles will bounce further. The particles in the two gases above are molecules. The mass of a molecule is called its relative molecular mass. So The lower its relative molecular mass, the faster a gas will diffuse. 2 The temperature When a gas is heated its particles take in heat energy, and move faster. They collide with more energy, and bounce further away. So the gas diffuses faster. The higher the temperature, the faster a gas will diffuse. Diffusion Download as PDF

fde85c58-101d-46eb-9a7c-0451dd29502c understand that chemical reactions are accompanied by enthalpy changes and these changes can be exothermic (ΔH is negative) or endothermic (ΔH is positive) Summary Chemical reactions are accompanied by enthalpy changes, which refer to the heat energy exchanged during the reaction. Enthalpy (H) represents the total energy content of a system, including both internal energy and the energy associated with pressure and volume. By studying enthalpy changes, we gain insights into the energy flow and transformations occurring in chemical reactions. Enthalpy changes can be classified as exothermic or endothermic based on the sign of ΔH, which represents the change in enthalpy. In exothermic reactions, the products have lower enthalpy than the reactants, resulting in a negative ΔH value. This negative ΔH indicates that the reaction releases heat energy to the surroundings. For example, when wood burns, it undergoes an exothermic reaction. The reactants (wood and oxygen) have a higher enthalpy than the products (carbon dioxide, water, and heat), leading to a negative ΔH. The heat released during this reaction warms up the surroundings, making it feel warm and giving off light. On the other hand, endothermic reactions have products with higher enthalpy than the reactants, resulting in a positive ΔH value. This positive ΔH indicates that the reaction absorbs heat energy from the surroundings to proceed. An example of an endothermic reaction is the process of photosynthesis in plants. During photosynthesis, plants convert carbon dioxide and water into glucose and oxygen using energy from sunlight. This reaction requires energy input, which is absorbed from the surroundings, resulting in a positive ΔH. Understanding whether a reaction is exothermic or endothermic is crucial for various applications. It helps us predict the energy changes associated with reactions and understand their impact on the surroundings. Exothermic reactions often have practical applications such as combustion for energy generation, while endothermic reactions are commonly utilized in processes like thermal decomposition or cooling systems. In summary, enthalpy changes in chemical reactions can be exothermic (ΔH is negative) or endothermic (ΔH is positive). Exothermic reactions release heat energy to the surroundings, while endothermic reactions absorb heat energy from the surroundings. By recognizing and understanding these enthalpy changes, we gain insights into the energy dynamics of chemical reactions and their significance in various real-world processes.

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

2f1a747a-a4ca-4373-9f32-39d6958d7e36 Effect of changing concentration on rate of reaction: Summary Increasing the concentration of a reactant 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.

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.

26b7b582-16a5-466e-adf7-f5ec8d0d28bd Most chemical reactions proceed by sequences of steps, each involving only two-particle collisions. Summary