Question

How much energy (in joules) is released when 0.06 kilograms of mercury is condensed to a liquid at the same temperature?

A. 20,075.04 J
B. 51,302.88 J
C. 17,705.1 J
D. 697.08 J
The correct answer is C
I just took the test and got it right.

Answer 1

The energy released when a certain amount of a substance condenses to a liquid is given by:

`Q=m \lambda_v`

where m is the mass of the substance and
`\lambda_v` is the latent heat of vaporization.

In this problem, the mass is m=0.06 kg, while the latent heat of vaporization of mercury is
`\lambda_v=296 kJ/ kg`. Therefore, if we apply the formula we get:

`Q=(0.06 kg)(296 kJ/ kg)=17.76 kJ=17760 J`

So, the correct answer is

C. 17,705.1 J