C8.4 - The effect of concentration or pressure

Question 1

What are some of the most beautiful buildings and statues made of?

Answer 1

Some of the most beautiful buildings and statues are made of:
1. Limestone
Or,
2. Marble

Question 2

Some of the most beautiful buildings and statues are made of limestone or marble.
What have these done?

Answer 2

These have stood for centuries

Question 3

Some of the most beautiful buildings and statues are made of limestone or marble.
These have stood for centuries.
However, what are they now doing?

Answer 3

They are now crumbling away at a greater rate than before

Question 4

Some of the most beautiful buildings and statues are made of limestone or marble.
These have stood for centuries.
However, they are now crumbling away at a greater rate than before.
Why is this?

Answer 4

They are now crumbling away at a greater rate than before, because both:
1. Limestone
2. Marble
are mainly calcium carbonate

Question 5

Some of the most beautiful buildings and statues are made of limestone or marble.
These have stood for centuries.
However, they are now crumbling away at a greater rate than before, because both limestone and marble are mainly calcium carbonate.
This reacts with acids, leaving the stone soft and crumbly.
Why has the rate of this reaction speeded up?

Answer 5

The rate of this reaction has speeded up, because the concentration of acids in rainwater has increased

Question 6

What does increasing the concentration of reactants in a solution do?

Answer 6

Increasing the concentration of reactants in a solution increases the rate of reaction

Question 7

Why does increasing the concentration of reactants in a solution increase the rate of reaction?

Answer 7

Increasing the concentration of reactants in a solution increases the rate of reaction, because there are more particles of the reactants moving around in the same volume of solution

Question 8

What happens the more ‘crowded together’ the reactant particles are?

Answer 8

The more ‘crowded together’ the reactant particles are, the more likely it is that they will collide

Question 9

The more ‘crowded together’ the reactant particles are, the more likely it is that they will collide.
So what does the increased frequency of collisions results in?

Answer 9

The increased frequency of collisions results in a faster reaction

Question 10

The more ‘crowded together’ the reactant particles are, the more likely it is that they will collide.
So the increased frequency of collisions results in a faster reaction.
What does increasing the pressure of reacting gases do?

Answer 10

Increasing the pressure of reacting gases has the same effect

Question 11

What does increased pressure do?

Answer 11

Increased pressure squashes the gas particles more closely together

Question 12

Increased pressure squashes the gas particles more closely together.
What are there in a given space?

Answer 12

There are more particles of gas in a given space

Question 13

There are more particles of gas in a given space.

What does this do?

Answer 13

This increases the chance that they will:

1. Collide
2. React

Question 14

There are more particles of gas in a given space.
This increases the chance that they will collide and react.
So what does increasing the pressure do?

Answer 14

Increasing the pressure produces more frequent collisions, which will increase the rate of the reaction

Question 15

What does increasing the concentration of solutions or the pressure of gases both mean?

Answer 15

Increasing the:
1. Concentration of solutions
Or,
2. Pressure of gases
both mean that particles are closer together

Question 16

Increasing the concentration of solutions or the pressure of gases both mean that particles are closer together.
What does this do?

Answer 16

This increases the frequency of collisions between reactant particles, so the reaction rate increases

Question 17

Some of the most beautiful buildings and statues are made of limestone or marble.
These have stood for centuries.
However, they are now crumbling away at a greater rate than before.
They are now crumbling away at a greater rate than before, because both limestone and marble are mainly calcium carbonate.
This reacts with what?

Answer 17

This reacts with acids

Question 18

Some of the most beautiful buildings and statues are made of limestone or marble.
These have stood for centuries.
However, they are now crumbling away at a greater rate than before.
They are now crumbling away at a greater rate than before, because both limestone and marble are mainly calcium carbonate.
This reacts with acids, leaving the stone what?

Answer 18

This reacts with acids, leaving the stone:

1. Soft
2. Crumbly

Question 19

Increasing the concentration of solutions or the pressure of gases both mean that particles are closer together.
This increases the frequency of collisions between reactant particles, so what increases?

Answer 19

This increases the frequency of collisions between reactant particles, so the reaction rate increases