IGCSE Chemistry - Reversible reactions and equilibrium

What type of reactions can able to change products back to the their original form?

• Reversible reactions

• Irreversible reactions

• Combustion reactions

• Combination reactions

Which of the following changes is irreversible change?

• Melting of ice cube

• Heating hydrated CuSO₄

• Frying an egg

• Thermal decomposing NH₄Cl

Which of the following combination is correct?

• reversible ⇌

  irreversible →

• reversible ←

  irreversible →

• reversible ⇌

  irreversible ←

• irreversible ⇌

  reversible →

If a reversible reaction is exothermic in the forward direction, it will be ...

• exothermic in the reverse direction

• endothermic in the forward direction too

• endothermic in the reverse direction

• not involve energy in reverse direction

Which of these is NOT a reversible change?

• Water to Ice
• Juice to ice lolly
• Cookie Dough to Cookie
• Melting Chocolate

A substance that increases speed of chemical reaction without being being changed is called:

• Catalyst
• Acid
• Base
• pressure

Increase in temperature of the reactants can do one of the following

• Slow collision frequency
• Allow less effective collision between the particles
• Cause particles to lose speed
• Increase collision between the particles thus increasing the rate.

What is the color of the reactant ?

• blue

• white

What is the color of product ?

• blue

• white

A temperature increase causes the particles ......

• to slow down

• move faster

• collide higher

• in the right order