Chemistry 6 (paper2)

Define rate of reaction

How quickly a reactant is used or how quickly a product is formed

What is the calculation for mean rate?

Amount of reactant used or product formed/ time taken

What is the calculation for mean rate 2?

1/time taken

If there is not enough —— chemical reactions can not take place as there is not enough ——

Energy

Activation energy

Why might particles collide more?

temperature

Pressure

Catalysts

Smaller surface area

Define collision theory

Particles colliding with enough energy to cause a chemical reaction

What is the disappearing cross experiment?

You put sodium thiosulphate in a test tube and heat it to a temperature (variable) and see how long it takes to react and disappear the cross

What does more collisions equal?

More energy

Why does changing pressure effect rate of reaction?

High pressure

Less space to move

More particles to collides with

Increased

Low pressure

More space

Longer to collide

Less frequent reactions

What was the method for the reversible reactions and equilibria?

Add a large spatula of copper sulphate to a test tube

Add mineral wool on top

Heat test tube on a blue flame until it turns gray

Let it cool and add distilled water

What should you expect to see in a reversible reaction experiment?

Turin it grey

Spark when water is added

Solids travel up to tube

Rehydrated

What is the equation for a reversible reaction experiment?

Hydrated copper sulphate —> dehydrated copper sulfate + water

Define dynamic reaction

An equilibrium reaction

Define equilibrium

Balanced reaction, same rate of reaction both ways

Define anhydras

Lack of water

What factors effect equilibrium?

Pressure

Temperature

Concentration

Catalyst

What is le chateliers principle?

Equilibrium shifts to reducing what you have increased, it will always do the opposite

What is the barber process?

Nitrogen based fertilisers need to make proteins

Lead to nitrogen fixing as nitrogen is insolvable in water so plants cant absorb it

Who was fritz harbour?

A German scientist who developed nitric acids into ammonia

What is ammonia made from?

Hydrogen

Nitrogen

Define fixing nitrogen

Turning it into a soluble from

When you decrease the temperature in the surrounding for equilibrium what happens?

Favour endothermic reaction

Increases temperature

When you increase the temperature ion the surroundings for equilibrium what happens?

Favours endothermic

Temperature decrease

What you increase pressure in equilibrium what happens?

Favour side with fewer molecules

Will decrease pressure

When you decrease pressure in equilibrium what happens?

favour side with more molecules

Increase pressure