Chemistry

Problem

18.0\,\text{g}

sample of a metal with molar mass

27.0\,\text{g}\,\text{mol}^{-1}

is heated to

105.0\,^{\circ}\text{C}

and transferred to

75.0\,\text{g}

of water at

20.0\,^{\circ}\text{C}

in a calorimeter whose heat capacity is

40.0\,\text{J}\,^{\circ}\text{C}^{-1}

. The system reaches a final temperature of

23.2\,^{\circ}\text{C}

. Using

4.18\,\text{J}\,\text{g}^{-1}\,^{\circ}\text{C}^{-1}

for water, what is the molar heat capacity of the metal? a)

18.4\,\text{J}\,\text{mol}^{-1}\,^{\circ}\text{C}^{-1}

28.2\,\text{J}\,\text{mol}^{-1}\,^{\circ}\text{C}^{-1}

20.7\,\text{J}\,\text{mol}^{-1}\,^{\circ}\text{C}^{-1}

9.2\,\text{J}\,\text{mol}^{-1}\,^{\circ}\text{C}^{-1}