How much energy does it take to convert \(0.500 \mathrm{~kg}\) of ice at \(-20 .{ }^{\circ} \mathrm{C}\) to steam at \(250 .{ }^{\circ} \mathrm{C}\) ? Specific heat capacities: ice, \(2.1 \mathrm{~J} \mathrm{~g}^{-1}{ }^{\circ} \mathrm{C}^{-1}\); liquid, \(4.2 \mathrm{~J} \mathrm{~g}^{-1}{ }^{\circ} \mathrm{C}^{-1}\); steam, \(2.0 \mathrm{~J}\) \(\mathrm{g}^{-1}{ }^{\circ} \mathrm{C}^{-1} ; \Delta H_{\text {vap }}=40.7 \mathrm{~kJ} / \mathrm{mol} ; \Delta H_{\text {fus }}=6.01 \mathrm{~kJ} / \mathrm{mol}\).