Question

A 50-g ice cube at -4

oC is dropped into an insulated container conatining 200mL at 25°CWhen thermal equilibrium is reached, the temperature of water dropped to 9°C. How much heat

is gained by the ice cube ?

Answer 1

Solution.

$m_c=0.05kg;$

$t_1=-4^oC;$

$t=9^oC;$

$V_w=0.2\sdot10^{-3}m^3;$

$t_2=25^oC;$

$Q_w^-=c_wm_w\Delta t;$

$m_w=\rho_wV_w;$

$m_w=10^3\sdot0.2\sdot10^{-3}=0.2kg;$

$Q_w^-=4200\sdot0.2\sdot(25-9)=13440J;$

$Q_c^+=Q_w^-=13440J;$

Answer: $13440J.$