Question

The boiling point of water in Kelvin scale is:
A) 73.15K
B) 173.15K
C) 273.15K
D) 373.15K

Answer 1

Hint: The boiling point of any substance is the temperature where the liquid gets converted into a vapor. It is the temperature at which the pressure exerted by the ambient on a liquid is equal to the pressure exerted by the vapor of the liquid; In this case, the change in heat changes the vapor without increasing the temperature.

Complete answer:
Boiling point of water is ${{100^\circ C}}$
To convert the kelvin scale, we have to add $273.15K$ to $^\circ C$ scale value.
So, The boiling point of water is ${{100^\circ C}}$.
Temperature on the Kelvin scale (K) = 273+ temperature on the Celsius scale
 ${{or, K = 273 + ^\circ C}}$
$\Rightarrow {{{T}}_{{k}}}{{ = t^\circ C + 273}}{{.15}}$
$\Rightarrow {{{T}}_{{k}}}{{ = 100^\circ C + 273}}{{.15}}$
$\therefore T_k = 373.15 K$

Hence option D is correct.

Note: An absolute scale is one where the measurement starts at a minimum or zero point and only progresses in one direction. For temperature measurement, the Kelvin (relative to the Celsius scale) and Rankin (relative to the Fahrenheit scale) scales are absolute temperature scales. These start at a moment where the molecular motion stops, the absolute zero point.