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Hint
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Answer
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9999999999999999999
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state the chemical equation for the production of magnesium sulfate from magnesium
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Mg + CuSO₄ ̣̣─> MgSO₄ + Cu
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9999999999999999999
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what is an endothermic reaction
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reaction that absorbs heat energy
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what is calorimetry
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measures amount of energy transferred in a chemical reaction
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what happens when hydrated copper (ii) sulfate is thermally decomposed
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forms water and anhydrous copper (ii) sulfate in an exothermic reaction
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what does ventilated mean
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an area that's air is well circulated
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what is water's c
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4.2 J/g °C
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what does an decrease pressure do to position of equilibrium
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shifts to side that produces more gas molecules
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what does the position of equilibrium depend on
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pressure and temperature of reactants
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how do we know if a catalyst is effective in the decomposition of hydrogen peroxide
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if bubbles of oxygen gas are formed
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what type of calcium carbonate should you use to get the fastest rate of reaction
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calcium carbonate powder
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what type of calcium carbonate should you use to get the slowest rate of reaction
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one big chunk of calcium carbonate
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what is the catalyst we use in the decomposition hydrogen peroxide
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manganese (IV) oxide (MnO₂)
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describe the combustion reaction of ethanol
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So, it combusts meaning it reacts with oxygen. This experiment measures how much energy is produced when a fuel is burnt. Our fuel is an alcohol and it is placed in a spirit burner. Use a thermometer to measure the temperature. The experiment goes as follows:
First, the spirit burner containing the alcohol is measured both together as one mass and recorded. Then 100cm³ of water is transferred into a copper container and it's initial temperature is measured and recorded. The spirit burner is lit and placed under the copper container. The water heats up. Water is stirred constantly with the thermometer until the temperature rises by what you wanted, let's say it was 30°C. After this value is reached, extinguish the flame and measure and record the maximum temperature. Finally, the spirit burner containing the remaining alcohol is re weighed again collectively, then subtract the final mass from the initial mass to get the amount of alcohol burnt. Let's say our water was at room temperature, so if the change in temperature is 30°C then our final temperature is 50°C. Let's say the mass of the spirit burner and alcohol was 34.46g and after it was 32.57g then we do 34.46 - 32.57 to get 1.89. So 1.89g of alcohol was burnt. As we know the specific heat capacity of water is 4.2J/g °C we can work out the energy transferred. So Q = mc△T substitute the values in to get 100 x 4.2 x 30 = 12,600. This means 1.89g of alcohol burns to produce 12,600J of energy. We can work out how much energy is released when we burn 1g of our alcohol by doing 12,600 ÷ 1.89 = 6666.67. So about 6700J is released when we burn 1g of our alcohol. The word equation is:
alcohol + oxygen ─> carbon dioxide + water |
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if forward direction is endothermic what is the backwards direction
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exothermic
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what will happen if you carry out the calcium carbonate and hydrochloric acid experiment but with half the concentration of acid
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the volume and mass of acid stays the same it's just more diluted, otherwise the experiment would measure how much volume affects the rate of reaction. the marble chips need to be in excess, this reaction happens slower as they are less acid particles per unit of volume so the marble chip particles have to travel further to react so it takes longer. It produces exactly half the carbon dioxide as before and takes longer to reach the horizontal line which indicates the termination of the reaction.
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state the △H, increased temperature change, energy of products and reactants and the type of reaction of
CH₄ + H₂O ⇌ CO + 3H₂ |
it's an endothermic reaction because the forward direction is endothermic, we know this because our H₂O and CH₄ molecules are no where to be seen, so they must've been broken and bond breaking is endothermic so our reaction is endothermic. An endothermic reaction has a positive △H because reactants have less energy than products because reactants lose energy to the products meaning the △H is positive. If temperature is increased the position of equilibrium shifts to the right. This is because an increase in temperature means the surroundings get hotter, an endothermic reaction absorbs heat, this will counteract the warmth. balancing it out, restoring equilibrium. So we want to shift the position of equilibrium to the endothermic direction. This is the right, so position of equilibrium shifts to the right. So more product is made.
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what does an increase temperature do to position of equilibrium
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shifts to endothermic direction
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how does a catalyst work
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provides an alternative pathway for the reaction to take place with a lower activation energy so the reaction can happen
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state the word equation between calcium carbonate and Hydrochloric acid in alphabetical order
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calcium carbonate + hydrochloric acid ─> calcium chloride + water + carbon dioxide
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describe and explain how to increase the rate of reaction with a liquid without increasing temperature
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Increase the concentration of the liquid, this means more particles will be in the same volume, so there will be more particles per unit of volume, this produces more frequent collisions which increases the rate of reaction.
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state the chemical equation between ethanol and oxygen
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C₂H₅OH + 3O₂ ─> 2CO₂ + 3H₂O
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state the word equation in the thermal decomposition of ammonium chloride
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ammonium chloride ⇌ nitrogen + hydrogen chloride
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what is conservation of energy
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energy isn't created or destroyed in a chemical reaction
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if energy is released by the forward direction then what is the backwards direction
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energy is absorbed
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what will happen if you carry out the calcium carbonate and hydrochloric acid experiment but with an increased temperature
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all the mass and volumes stay the same, just the temperature increases. The rate of reaction is much quicker than before, happens faster and reaches the end of the reaction very quickly, so it plateaus faster.
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what's a bond energy
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strength of a chemical bond
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what is a reaction profile a.k.a
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energy level or energy profile
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how does the position of equilibrium change when there's an increase in pressure of this reaction:
CH₄ ₍₉₎ + H₂O₍₉₎ ⇌ CO₍₉₎ + 3H₂ ₍₉₎ |
first, see what side has more molecules of gas. 4 molecules on right and 2 molecules on left. So if pressure increases, position of equilibrium shifts to the left. This is because an increase in pressure means there is less space for molecules, so if we produce less particles we can decrease the pressure, this cancels out the increase in pressure so equilibrium is restored and more reactant is produced because it has less gas molecules.
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in an endothermic reaction, is △H negative or positive
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positive
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what does an decrease temperature do to position of equilibrium
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shifts to exothermic reaction
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in what reaction do reactants have more energy than products
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exothermic reaction
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why do reactants have more energy than products sometimes
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reactants give heat energy to surroundings which warms the surroundings
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99999999999999999999
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describe how to carry out experiment between sodium thiosulfate and hydrochloric acid
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1: draw a large cross onto a piece of paper 2: place a conical flask onto the cross 3: pour sodium thiosulfate and hydrochloric acid into the beaker 4: observe the reaction directly above the flask 5: record the time taken for the cross to vanish 6: the cross vanishes because the yellow sulfur precipitate is formed |
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what is x⁻¹ the same as
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1/x
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what does the energy released by the forward direction equal
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energy absorbed by the backward direction
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what is a catalyst
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a substance that increases the rate of reaction without getting chemically changed in the process, so it isn't used up and can be used again as a catalyst.
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describe the neutralisation experiment using a polystyrene cup with magnesium and copper (ii) sulfate
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First, 50cm³ of copper (II) sulfate is measured and placed into a polystyrene cup Secondly, the initial temperature of the copper (II) sulfate solution is measured and recorded. Thirdly, Magnesium is added and the maximum temperature is measured and recorded Finally, the temperature rise is calculated We use a polystyrene cup because it is an insulator and our reaction is exothermic so this cup will keep all the heat inside and not let loads escape, so it reduces heat loss. This experiment covers neutralisation, displacement and dissolving a salt. |
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if a reversible reaction is endothermic one way what will the other way be
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exothermic
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how do we see what catalysts are the best at decomposing hydrogen peroxide
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experiment with different catalysts
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what is the difference in energy known as in a reaction profile
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△H
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what is the symbol reversible equation for the reaction between hydrogen and nitrogen
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hydrogen + nitrogen ⇌ ammonia
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what is room temp. (don't use kelvin)
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20°C
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what does an increase pressure do to position of equilibrium
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shifts to side that produces fewer gas molecules
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what can the units of rate of reaction be
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what one thing do reactions need to take place
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activation energy
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define the rate of reaction
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how quickly the products are formed or how quickly the reactants are used up
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what will happen if you carry out the calcium carbonate and hydrochloric acid experiment but with bigger marble chips with a total mass of the same before, like you have joined the smaller marble chips together
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these bigger marble chips have a smaller surface area, so reaction will be slower. The same carbon dioxide is produced as it has the same mass, but it takes longer for it to reach the maximum carbon dioxide produced. So it takes longer for the line to plateau or become flat. It is less steep to begin, showing it's slower than before.
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what precipitate forms when sodium thiosulfate and hydrochloric acid react
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yellow sulfur precipitate
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what does △H mean
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(molar) enthalpy change
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in an exothermic reaction, is △H negative or positive
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negative
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