Question

How much heat energy in joules J is necessary to raise the temperature of 5 kg of water from 20°C to 100°C?
1674.4 kJ
167440 kJ
16720 kj
16744 kJ​

Answer 1

Explanation:

Given,

m=5kg=5,000g

ΔT=1000C−200C=800C

The magnitude of heat energy in joule is H

H=4.186×5000×80=1672400J

H=1672×103=1672KJ

Answer 2

Answer:

Explanation:

. Given: Mass (m) = 5 kg

Temp. difference (∆T) = 100 - 20 = 80°C

Specific heat capacity (c) = 1 kcal/kg°C

To find: Heat energy (Q) = ?

Formula: Q = mc∆T

Solution:Q = 5 × 1 × 80

= 400 kcal