Question

How much energy will it take to melt $100$ grams of ice at ${0^\circ }C$?

Answer 1

In order to solve this question we need to know the relation between energy and mass of an object. Here, in this case we need to consider the heat energy as we are required to melt the given mass of the ice. For that we need to know the relation between the heat energy and the mass of an object. After solving the equation obtained, we can finally conclude with the correct solution of the given question.

Complete step by step answer:
Step one
The mass of the ice in the question is given as,$m = 100g = \dfrac{{100}}{{1000}} = 0.1kg$
Step two
We know that heat energy of an object can be given by,
$Q = Lm$………….. (i)
Where $L$ is the latent heat of the body. Here, we are considering ice. So, we need to know the value of latent heat of the ice.
The latent heat of ice is ${L_{ice}} = 3.34 \times {10^5}Jk{g^{ - 1}}$
Step three
Now, we need to put the values of the mass and latent heat of the ice in equation (i).
After putting the values in equation (i), we get,
$Q = 3.34 \times {10^5} \times 0.1$
$\therefore Q = 33400J = 33.4kJ$
Therefore, the required energy for melting the ice is $33.4kJ$.

Note:
Heat can be defined as the form of energy which is transferred between the objects with different temperatures. The heat energy can be transferred from one body to another body. We can define latent heat of an object as the amount of heat required to convert a solid into a liquid or vapour or to convert a liquid into vapour state without changing the temperature.