Free account: track your progress — Sign up free

WAEC Chemistry 2022 Objective — Question 44

Question 44 of 50 from the West African Examinations Council (WAEC) Chemistry 2022 Objective paper, with the correct answer and a full explanation.

Advertisement

Consider the following table: Substance | Melting point/°C | Boiling point/°C P | −78 | −25 Q | −8 | 40 R | −6 | 150 S | 44 | 280 Which of the substances is a liquid at room temperature and rapidly evaporates on exposure to air?

  • A. P
  • B. QCorrect
  • C. R
  • D. S

Explanation

Since the boiling point of Q is 40°C, it will still remain in the liquid form at room temperature (25°C), but the air temperature can easily be raised to 40°C to cause it to evaporate — making Q a liquid that rapidly evaporates.

Advertisement

Sign up free to unlock

  • Score tracking
  • Practice history
  • Saved questions
  • Progress dashboard
  • Personalized sessions
  • Weak-topic breakdown

…and/or go further with premium services and No Ads.