The heat required : 840 J
Further explanation
Given
mass of water = 20 g
Temperature : 30°C to 40°C
Required
Heat to raise the temperature
Solution
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C (for water= 4.18 J/g° C)
∆T = temperature difference, ° C / K
The heat :
[tex]\tt Q=20\times 4.2\times (40-30)\\\\Q=\boxed{\bold{840~J}}[/tex]
