Reversible reactions

Question 1

A + B ⇌ C + D

• What do this show? part 1

Answer 1

• reversible reaction
• As reactant reacts , their concentration fall = forward reaction slow down.
• But as more products are made and their concentration rises, the backward reaction will speed up
• After a while, both forward reaction and backward one are at exactly same rate = system is at equilibrium

Question 2

A + B ⇌ C + D

• What do this show? part 2

Answer 2

• At equilibrium both reactions are still happening, but, there’s no overall effect.
• This means concentrations of reactants and products reach a balance and won’t change
• Equilibrium only takes place if reversible reaction takes place in closed system
  -( Define closed system )

Question 3

When a reactions at equilibrium, are both amounts of reactants and products the same ?

Answer 3

• No
• If equilibrium lies to the right, concentration of products is greater than that of the reactions
• VICE VERSA

Question 4

What does the position of equilibrium depend on?

Answer 4

• The following conditions
  ⭐ temperature
  ⭐ pressure
  ⭐ concentration of reactants and products

Question 5

e.g. Ammonium chloride ⇌ ammonia + hydrogen chloride
Effect of temperature

Answer 5

Heating this reaction moved equilibrium to the right and cooling it moves it to the left.

Question 6

Reversible reactions can be —– and ———-

Answer 6

endothermic, exothermic

Question 7

What happens if your reaction is endothermic in one direction?

Answer 7

• It will be exothermic in the other
  The energy transferred from the surrounding by the endothermic reaction is equal to the energy transferred to the surrounding during exothermic reaction

Question 8

Thermal decomposition of hydrated copper sulphate
hydrated copper sulphate (endothermic -> )( exothermic <-) ⇌( exothermic <-) (endothermic -> ) anhydrous copper sulphate + water

Answer 8

-If you heat blue hydrated copper (II) sulphate, it drives water off and leaves white anhydrous copper (II) sulphate powder. = endothermic

If you add couple drops of water to white powder, you get the blue crystals back = exothermic