Question

If the specific heat of mercury is 0.14 J/g$^\circ C$, how much heat is required to raise the temperature of 250.0 g of mercury from $10^\circ C$ to $62^\circ C$?

Answer 1

Hint: The specific heat is denoted by “C” which is defined as the amount of heat required per unit mass to raise the temperature by one degree Celsius. The heat absorbed is calculated by multiplying the mass with the specific heat and change in temperature.

Complete step by step answer:
Given,
Specific heat of mercury is 0.14 J/g$^\circ C$.
The mass of mercury is 250.0 g.
The temperature change is ($62^\circ C$-$10^\circ C$) =$52^\circ C$
The specific heat is defined as the amount of heat needed per unit mass to raise the temperature by one degree Celsius. The unit of specific heat is $JK{g^{ - 1}}{K^{ - 1}}$
The relation between the heat and temperature change is given by the formula relating with the specific heat.
The formula is shown below.
$Q = m.c.\Delta T$
Where,
Q is the heat absorbed.
m is the mass
c is the specific heat
$\Delta T$ is the change in temperature.
As we are given all the values, the heat required to raise the temperature of 250.0 g of mercury from $10^\circ C$ to $62^\circ C$ can be calculated easily just by substituting the values in the formula.
$\Rightarrow Q = 250.0 \times 0.14 \times 52$
$\Rightarrow Q = 1820J$
The answer obtained is in joule so it will be converted to two significant figures and expressed in kilojoules.

Therefore, heat is required to raise the temperature of 250.0 g of mercury from $10^\circ C$ to $62^\circ C$is 1.8 KJ.

Note: The specific heat of the water is 1 calorie/gram degree Celsius which is greater than the specific heat of any other common substance. This is why the water plays a very important role in temperature regulation.