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Flashcards in Reactions Deck (15)
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1
Q

What happens when reactants reverse themselves and what is it called?

A

Reactants reverse themselves and the products change back to being reactants again, this is called a reversible reaction

2
Q

What is the calculation to work out the percentage of yield?

A

Yield
(divided by) x100
expected yield

3
Q

What is an example of an exothermic reaction?

A

Hand warmers using oxidation of iron

4
Q

What is an example of an endothermic reaction?

A

An instant cold pack

5
Q

What are the 3 ways you can measure a reaction?

A

Mass
Volume
Light transmitted

6
Q

What factors speed up reactions?

A
Increased temperature
Increased concentration of dissolved reactants 
Increased pressure of gaseous reactants 
Increased surface area 
Use of a catalyst
7
Q

What does the rate of a reaction depend on?

A

The frequency of collisions between particles

The energy with which particles collide

8
Q

What are catalysts?

A

Catalysts are substances that change the rate of a reaction without being used up in a reaction

9
Q

How do catalysts work?

A

By lowering the activation energy of a reaction

10
Q

What is an exothermic reaction?

A

A reaction or process accompanied by the release of heat and an increase of outside temperature

11
Q

What is an endothermic reaction?

A

A reaction or process accompanied by the absorption of heat and a decrease in surrounding temperature

12
Q

Finish the sentence… Exothermic is where…

A

Heat is let out

13
Q

Finish … Endothermic is where…

A

Heat is taken in

14
Q

What does breaking bonds mean?

A

Energy is being used

15
Q

What does making bonds mean?

A

Energy is lost