Question

Which of the following is a correct observation when water added to quick lime?

• A. Vigorous bubbling and a hissing sound. both
• B. Slow bubbling with no sound
• C. Vigorous bubbling with evolution of heat hissing sound
• D. No change

Answer 1

Answer: (C)

Vigorous bubbling with evolution of heat hissing sound

Quicklime is chemically Calcium Oxide. When water is added to Quick lime,calcium hydroxide is formed and a lot amount of heat is released in this process. A hissing sound is also observed.

THe reaction is,

$CaO+H_{2}O\to Ca(OH{)}_2+Heat$