Question

Calculate the amount of energy required to boil 25.00 g of mercury.

Answer 1

C. 7.4 kJ

Step-by-step explanation:

Let assume that Mercury is at room temperature (25 °C). The energy required to boil the sample of mercury is the sum of sensible and latent heats. Mercury has a fussion and boiling points of -38.83 °C and 356.7 °C, respectively, and a specific heat of
`138\,(J)/(kg\cdot ^(\circ)C)`. Then:

`Q = (25\,g)\cdot \left[\left(0.138\,(J)/(g\cdot ^(\circ)C) \right)\cdot (356.7^(\circ)C - 25^(\circ)C) + 296\,(J)/(g) \right]`

`Q = 8544.365\,J`

The option that offers the best approximation to the result is C.