Question

How much heat is required to increase the temperature of 100.0 grams of iron from 15.0oC to 40.2oC? (The specific heat of iron is 0.46 J/g xoC).

Answer 1

Ans: Heat required = 1159.2 J or 1.16 kJ

Given:

Mass of iron, m = 100.0 g

Initial temp, T1 = 15.0 C

Final temp, T2 = 40.2 C

specific heat of iron, c = 0.46 J/gC

To determine:

Heat required, q

Explanation:

Heat required is given as:

q = mcΔT

$q = 100.00 g * 0.46 J/gC * (40.2-15.0) C \\\\q = 1159.2 J$

Answer 2

The formula you need is: heat= specific heat x mass x ΔT

specific heat= 0.46 j/g-C
mass= 100.0 grams
ΔT= 40.2 - 15.0= 25.2C

heat= (0.46) x (100.0) x (25.2)=  1159.2 joules or 1200 joules (rounded off)