Q. The molar heat capacity of water at constant pressure is $75\ JK^{- 1}\ mol^{- 1}$. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand the increase in temperature of water is
A) 2.4 K
B) 3.6 K
C) 4.8 K
D) 1.2 K
Explanation
(a)
Heat capacity of water per gram $= \frac{75}{18} = 4.17$ J
$Q = mst = 100 \times 4.17 \times t = 1000$
$t = \frac{1000}{100 \times 4.17} = 2.4\ K$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.