The molar volumes of solid and liquid lead at the normal melting temperature of lead are, respectively, 18.92 and 19.47 cm3. calculate the pressure

We use the formula:

ΔP = (ΔH / ΔV) ln (T2 / T1)

where,

ΔH = change in enthalpy from solid to liquid = 4810 J/mol

ΔV = change in volume from solid to liquid = 0.55 cm^3/mol

T2 = 620 K, T1 = 600 K

So,

ΔP = (4810 / 0.55) ln (620 / 600)

ΔP = 286.76 J/cm^3

or converting to atm:

ΔP = 2830 atm