How can relative amounts of energy released when substances burn be measured by?
Simple calorimetry. Eg. by heating water in a glass or metal container. The method can be used to compare the amount of energy released by fuels and foods.
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What can the equation Q=mcΔT be used for?
Calculating and comparing the amount of energy released by different fuels
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What is energy usually measured in?
Joules(J).
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How can the amount of energy released or absorbed by a chemical reacton in solution be calculated?
From the measured temperature change of the solution when the reagents are mixed in an insulated container. This method can be used for reactions of solids with water or for neutralisation reactions.
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What can simple energy level diagrams be used for?
To show the relative energies of reactants and products, the activation energy and the overall energy change of a reaction.
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Is energy required or released during bond making?
Energy is released.
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Is energy required or released during bond breaking?
Energy is required.
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In an exothermic reaction, is the amount of energy required for bond breaking more or less than being released in bond making?
The energy released from forming new bonds is greater than the energy needed to break existing bonds.
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In an endothermic reaction, is the amount of energy required for bond breaking more or less than being released in bond making?
The energy needed to break existing bonds is greater than the energy released from forming new bonds.
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What do catalysts do?
Provide a different pathway for a chemical reaction that has a lower activation energy.
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How can hydrogen be burned as a fuel?
In combustion engines.
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What is the equation for burning hydrogen as a fuel?
hydrogen + oxygen --> water
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How else can this reaction be used?
In fuel cells that produce electricity to power vehicles.
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Other cards in this set
Card 2
Front
What can the equation Q=mcΔT be used for?
Back
Calculating and comparing the amount of energy released by different fuels
Card 3
Front
What is energy usually measured in?
Back
Card 4
Front
How can the amount of energy released or absorbed by a chemical reacton in solution be calculated?
Back
Card 5
Front
What can simple energy level diagrams be used for?
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