Question

Assuming that the heat capacities don't change with temperature, how much energy in kilojoules is needed to heat 7.70 g of Hg from a temperature of 58 to 51

Answer 1

Answer : The energy needed is, $7.55\times 10^{-3}kJ$

Explanation :

Formula used :

$q=m\times c\times (T_{final}-T_{initial})$

where,

q = heat needed = ?

m = mass = 7.70 g

c = specific heat = $0.140J/g^oC$

$T_{final}$ = final temperature = $58^oC$

$T_{initial}$ = initial temperature = $51^oC$

Now put all the given values in the above formula, we get:

$q=7.70g\times 0.140J/g^oC\times (58-51)^oC$

$q=7.546J=7.55\times 10^{-3}kJ$

Thus, the energy needed is, $7.55\times 10^{-3}kJ$