Energy in chemical reactions Flashcards Preview

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Flashcards in Energy in chemical reactions Deck (12)
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1
Q

endothermic reaction

A

one that takes in heat eg sherbet with water

2
Q

exothermic reaction

A

one that gives out heat eg. burning coal

3
Q

Collision Theory

A

for a reaction to occur, the reacting particles must collide with each other

4
Q

effective collision

A

one that results in the formation of products when the activation energy is reached

5
Q

Activation energy

A

the minimum energy which colliding particles must have for a reaction to occur

6
Q

effect of heat on chemical reactions , explained

A

At a higher temp, colliding particles move more quickly
so they have more energy
so the amount of effective collisions is increased
so chemical reactions are faster

7
Q

energy profile diagram

A

a graph that shows the change in energy of a reaction, as time passes, while the reaction takes place

8
Q

how does a catalyst work

A

provides an alternative route for the reaction to occur which has a lower Activation Energy , so the rate of reaction increases

9
Q

why would a graph be endothermic

A

if the energy of the products is higher than the energy of the reactants

10
Q

traingle H

A

delta (change) in heat

11
Q

whats the symbol used for activation energy

A

EA

12
Q

small activation energy means..

A

a large number of molecules have enough energy to pass over this energy barrier, so the rate of reaction is quick