The specific latent heat of fusion of ethyl alcohol is 100 Jg^-1. Find the heat absorbed (in J) by 2.25 g of ethyl alcohol when it melts at its melting point of -114°C.

Question

Question

This question was previously asked in

RRB ALP Fitter 23 Jan 2019 Official Paper (Shift 2).

Attempt Online

Answer 1

Explanation:

Sensible heat:

Sensible heat is defined as the amount of heat or energy required to change the temperature of the substance without changing the phase of the substance.
Mathematically, it can be represented by:

Q = m × c × ΔT

Q = Heat gain or loss, m = mass, c = specific heat, ΔT = Change in temperature

Latent heat:

It can be defined as a system that shows the phase transition.
It describes the changes that occur in the internal energy of the system.
At a constant temperature, during phase transition, the amount of heat absorbed or released is called latent heat.

Mathematically, it can be represented by:

Q = m × L_H

Where m = mass, LH = Specific Latent heat

Calculation:

Given:

Specific Latent heat, LH = 100 Jg-1, mass, m = 2.25 gm

Q = m × LH

⇒ Q = 2.25 × 100 = 225 J

Download Solution PDF