How much heat must be spent on the conversion of 200 g of mercury into steam taken at a temperature of 57 ° C?

To solve the problem, we apply the formula for determining the amount of heat with changes in the heating temperature of the substance:

Q = c * m (t2 – t1), where:

m – body weight, expressed in kilograms m = 200 g = 0.2 kg,
s = 140 J / (kg * deg) – specific heat of mercury,
t1 – initial temperature of mercury,
t2 is the final temperature of the vaporous mercury.
Let’s substitute the data into the formula in the SI system and determine the required amount of heat.

Q = 140 * 0.2 * (100 – 57) = 28 * 43 = 1204 J.