Rate Of Chemical Change

Question 1

Describe rate of reaction

Answer 1

Higher temp
= faster reaction
= as particles have more energy
= move around faster
= more frequent successful collisions

Question 2

Describe reaction depending of surface area

Answer 2

Larger surface area
= faster rate of reaction
= more particles available to react
= more successful collisions

Question 3

Describe effects of pressure on reactions

Answer 3

Higher pressure/ concentration
= faster rate of reaction
= more particles in a fixed volume
= higher chance of successful collisions

Question 4

Effect of catalyst

Answer 4

Lowers activation energy
= easier for reaction to take place

Question 5

Describe le chatiliers principle

Answer 5

Whatever you do to a reversible reaction the reaction will do the opposite

Question 6

Why is mass lost when gas produced

Answer 6

Gas produced
= escapes from the flask

Question 7

Why do polyesters melt when heated

Answer 7

Polyester is thermosoftening
Polyester has no cross links

Question 8

Why do polyesters melt when heated

Answer 8

Polyester is thermosoftening
Polyester has no cross links

Question 9

How does catalyst increase rate of reaction

Answer 9

Provides different reaction pathway which has lower activation energy

Question 10

Explain change of rate of reaction of sodium carbonate and hydrochloric acid

Answer 10

acid particles used up
so concentration decreases
less frequent collisions
so rate decreases