Question

Mercury turns to a vapor at 629.88 K. How much heat is lost when 75.0 g of mercury vapor at 650 K condenses to a liquid at 297 K?

Answer 1

- 3706.5 J.

Explanation:

The heat lost by the copper can be calculated using the formula:

Q = m.C.ΔT, where,

Q is the amount of heat lost by the mercury,

m is the mass of the copper (m = 75.0 g),

C is the specific heat of Hg (C = 0.140 J/g.°C),

ΔT is the temperature difference (the final temperature - the initial temperature (ΔT = (297 K - 273) °C - (650 K - 273) °C = - 353 °C).

∴ The amount of heat lost by the mercury Q = m.C.ΔT = (75.0 g) (0.140 J/g.°C) (- 353 °C) = - 3706.5 J.