Question

Describe an activity to observe what happens when quick lime is added to water taken in a beaker. State two important observations and name the type of reaction taking place.

Answer 1

i. Take small quantity of quick lime (CaO) in a beaker.
ii. Slowly add water to thequick lime (CaO) taken in the beaker.
iii. Touch the beaker with fingers and make a note of the change in temperature.

Observations:
i. Quick lime reacts vigorously with water producing hissing sound.
ii. Beaker becomes hot.

 Inferences:

 Quick lime (calcium oxide) reacts with water vigorously to form calcium hydroxide and releases large amount of heat.

 It is an example of a combination reaction as well as an exothermic reaction.