Answer
179 J of heat are released.
Work Step by Step
1. Calculate or find the molar mass for $ Hg $:
$ Hg $ : 200.6 g/mol
- Using the molar mass as a conversion factor, find the amount in moles:
$$ 20.1 \space g \times \frac{1 \space mole}{ 200.6 \space g} = 0.100 \space mole$$
2. Accordin to Table 15.3, the melting point of mercury is 234.32 K.
25.0 C = (25.0 + 273.15) K = 298.2 K
3. Calculate q:
q = n * $C_p$ * $\Delta T$
q = ( 0.100 mol)( 28.0 J/(mol K))( 234.32 K - 298.2 K)
q = $ -179 $ J
