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Correct Statement 1

ACTSCI-AMHSKQ

A new compound is discovered and a chemistry student undertakes a project to study its behavior when it is heated.

Setup

He places 2 grams of this compound in a container fitted with a piston. The piston is exposed to the atmosphere and thus the contents of the container will experience a constant pressure at all times. The walls of the container encase a heating filament, the rate of heat supplied by which can be changed.

Experiment 1

Constant heat was supplied at 500 watts to 2 grams of the compound and the rise in temperature was plotted against time.

Figure 1

Experiment 2

Constant heat was supplied at 1000 watts to 2 grams of the compound and the rise in temperature was plotted against time.

Figure 2

Note: In the figures, B and D are the melting and the boiling points respectively.

The student then conducted the experiment at various heating rates. He then plotted the times required to reach the melting and boiling points against the rate of heating of the compound.

Figure 3

Experiment 3

When the compound was completely converted into gas, the student measured the change in volume with increase in temperature. He plotted the volume of the gas against the temperature of the gas and obtained the following graph.

Figure 4

Based on the information given in the passage, which of these is correct?

A

The boiling point of the compound decreases as the rate of heating increases.

B

The enthalpy of fusion of the substance decreases with an increase in the heating rate from 500 watts to 1000 watts.

C

The plot of the time required to reach the melting point against the rate of heating follows the equation y = mx.

D

The latent heat of vaporization of the compound remains unchanged irrespective of the rate of heating.