The molar heat capacity of water at constant pressure is 84 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

Question

The molar heat capacity of water at constant pressure is 84 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) 3.8 K (B) 2.1 K (C) 4.8 K (D) 1.5 K

Tardigrade Admin · Accepted Answer

Molar heat capacity of water per gram =84 / 18=4.7 J As we know that; q=1 kJ =1000 J molar heat capacity (q)=m × c × Δ T where m= mass, c= specific heat capacity Δ T= temperature change ∴ q=100 × 4.7 × Δ T or 1000=100 × 4.7 × Δ T Δ T=(1000/100 × 4.7)=2.1 K Thus, the increase in temperature of water is 2.1 K.

Q. The molar heat capacity of water at constant pressure is $84 J K^{- 1} m o l^{- 1}$ . When $1.0 k J$ of heat is supplied to $100 g$ of water which is free to expand; the increase in temperature of water is

$3.8 K$

$2.1 K$

$4.8 K$

$1.5 K$

Q. The molar heat capacity of water at constant pressure is 84JK−1mol−1. When 1.0kJ of heat is supplied to 100g of water which is free to expand; the increase in temperature of water is

3.8K

2.1K

4.8K

1.5K

Molar heat capacity of water per gram =84/18=4.7J As we know that; q=1kJ=1000J molar heat capacity (q)=m×c×ΔT where m= mass, c= specific heat capacity ΔT= temperature change ∴q=100×4.7×ΔT or 1000=100×4.7×ΔT ΔT=100×4.71000​=2.1K Thus, the increase in temperature of water is 2.1K.

Q. The molar heat capacity of water at constant pressure is $84 J K^{- 1} m o l^{- 1}$ . When $1.0 k J$ of heat is supplied to $100 g$ of water which is free to expand; the increase in temperature of water is

$3.8 K$

$2.1 K$

$4.8 K$

$1.5 K$