Chemical Reactions: Reversible reactions

Question 1

What are hydrated salts?

Answer 1

Salts that have water as a part of their structure

Question 2

What is water in crystallisation?

Answer 2

Water in the salt

Question 3

What is anhydrous?

Answer 3

without water

Question 4

What happens when crystals are heated?

Answer 4

water in crystallisation is lost?

Question 5

What happens when you heat crystals of blue copper (II) sulfate?

Answer 5

they decompose to form a white powder

Question 6

What is the word equation for the heating of hydrated copper (II) sulfate?

Answer 6

hydrated copper (II) sulfate => (heat) => anhydrous copper (II) sulfate (white + water

Question 7

What is the symbol equation for the reversible heating of hydrated copper (II) sulfate?

Answer 7

CuSo4.5H2O (s) => (forward/backward) CuSo4 (s) + 5H2o (l)

Question 8

What is equilibrium?

Answer 8

Reactions in which both forward and reverse reactions are occurring

Question 9

What are the features of equilibrium reaction?

Answer 9

1. Products/ Reactants must not escape, reaction in closed system
2. At equilibrium, reactants are continually being changed to products and products back to reactants (dynamic equilibrium)
3. At equilibrium concentration of reactants and products do not change (same as the start), as rate of forward reaction = rate of reverse reaction
4. Equilibrium can be approached from either direction

Question 10

What is the position of equilibrium? (3)

Answer 10

Position of equilibrium tells how far reaction goes in favour of reactants or products/
Concentration of products greater => position of equilibrium to the right.
Concentration of reactants greater => position of equilibrium to the left.

Question 11

When the concentration of reactant is increased, where does equilibrium move and why

Answer 11

equilibrium moves to the right, to form more products until equilibrium is restored - keeps relative concentrations of products and reactants the same as before

Question 12

When the concentration of product is increased, where does equilibrium move?

Answer 12

equilibrium moves to the left to form more reactants

Question 13

What reactions can pressure only affect?

Answer 13

reactions where there is a gas in the equation

Question 14

If there are equal volumes or moles of gas on both sides of the equation, what is the effect of increasing pressure?

Answer 14

no effect

Question 15

In (2SO2 + O2 => 2SO3), where does an increase in pressure do?

Answer 15

moves the reaction to the write , more SO2 and O2 combine to form SO3

Question 16

If a reaction is exothermic in the forward direction, what will it be in the reverse reaction?

Answer 16

Endothermic

Question 17

For an forward exothermic reaction, when temperature increases, where does equilibrium shift?

Answer 17

Equilibrium shifts in favor of the reverse reaction

Question 18

For an forward endothermic reaction, when temperature increases, where does equilibrium shift?

Answer 18

Equilibrium moves to the right to favor products.