C6

Question 1

What is rate of reaction

Answer 1

How fast reactants are changed into products

Question 2

What do reaction graphs represent

Answer 2

The amount of product formed or reactants used up over time

Question 3

What is collision theory

Answer 3

When particles collide with enough activation energy to react. The more frequent the collisions are, the faster the reaction is. Energy is transfered between particles so particles must have enough ectivation energy in order for reaction to occur

Question 4

What are the 4 things that affect rate of reaction

Answer 4

. Tempurature
. Concentration
. Surface area
. Catalyst

Question 5

How does temp affect the rate of reaction

Answer 5

Increase temp means particles move faster as have more kinetic energy. Leads to more successful collisions occuring so rate increase

Question 6

How does increasing concentration and pressure increase reaction rate

Answer 6

More concentration means more particles so more particles to collide with so successful collisions occur more frequently
Increase pressure means more particles in a smaller space. This means there is more frequent collisions with walls and other particles

Question 7

How does increasing surface area increase reaction rate

Answer 7

More surface area means more surface to collide with so collisions occur more frequently

Question 8

How does using a catalyst increase reaction rate

Answer 8

. Speed up reaction rate without being used up. They decrease amount of activation energy needed for reaction to occur. They do this by providing alternate pathway with lower activation energy

Question 9

What is the equation for finding out the rate of a reaction

Answer 9

Amount of reactant used or product formed divided by time

Question 10

What are the 3 ways to measure the rate of reaction

Answer 10

. Precipitation and colour change
. Change in mass if gass given off
. Measure volume of gass given off - done using gass siringe. The more gass given off, the faster the reaction

Question 11

Magnisium and hydrochloric acid practical

Question 12

Sodium thiosulfate and hydrochloric acid practical

Question 13

How do u calculate the mean reaction rate from a graph

Answer 13

Overall change in y value ÷ time take

Question 14

How do u find the rate of a reaction at a particular point on a graph

Answer 14

Draw Tangent and find gradient

Question 15

What is a reversable reaction

Answer 15

A reaction where the products created can turn back into the reactants

Question 16

What is equalibrium

Answer 16

Tells us how many reactants there are compared to how many products there are. When equalibrium lie to the right, it means concentration of products greater than can concentration of reactants. Of lie to the left it’s the opposite

Question 17

What else can reversable reactions be

Answer 17

Exothermic - to the right
endothermic - to the left

Question 18

What is chanteliers principle

Answer 18

It is the idea that if you change the conditons of a reversable reaction at equalibrium, the system will try to counteract that change

Question 19

How can chanteliers principle be used to predict the affect of change in temp you make to a reaction system

Answer 19

Decrease temp - equalibrium shift to exothermic side to produce more heat
Increase - shift to endothermic side to decrease it

Question 20

How can chanteliers principle be used to predict the affect of change in pressure you make to a reaction system

Answer 20

. Only affects equalibrium involving gasses
. Increase - equalibrium shift to side with fewer gass molecules
. Decrease - move to side with more gass molecules

Question 21

How can chanteliers principle be used to predict the affect of change in concentration you make to a reaction system

Answer 21

Increase concentration reactants - produces more products
. Decrease consentration of products - reduce concentration of reactants