Answer:
2100 J
Explanation:
The heat required to increase the temperature of a substance is given by
[tex]Q=mC\Delta T[/tex]
where
m is the mass of the substance
C is its specific heat capacity
[tex]\Delta T[/tex] is its change in temperature
For the water in this problem, we have:
m = 100 g is its mass
C = 4.2 J/g • °C is the specific heat capacity
[tex]\Delta T=5^{\circ}C[/tex] is the increase in temperature
So, the amount of heat needed is:
[tex]Q=(100)(4.2)(5)=2100 J[/tex]