WBCS.LIVE practice question

Two drops of liquid merge to form a single drop. In this process energy is:

Solve this multiple-choice question and check the correct answer with its explanation below.

Answer options

  1. Absorbed.
  2. Released.
  3. May be absorbed or released depending upon the specific heat of the liquid.
  4. Neither absorbed nor released.

Correct answer and explanation

Correct answer: Released.

Explanation: When two liquid drops merge, energy is released due to decrease in surface area. 📚 Other Information: ▪️ Surface tension causes energy to be released when drops combine. ▪️ The surface area of a single big drop is less than two small ones. ▪️ This release of energy stabilises the larger drop. ▪️ Reverse process (splitting) requires absorption of energy. ▪️ Merging of raindrops in clouds is an example. ▪️ This principle is also applied in emulsions and colloid chemistry. ▪️ Cohesive forces between molecules hold the liquid together. ▪️ Energy release explains why merging is a spontaneous process.