Question

Calculate the amount of heat required to completely sublime 40.0 g of solid dry ice (co2) at its sublimation temperature. the heat of sublimation for carbon dioxide is 32.3 kj/mol.

Answer 1

The amount of heat required for the sublimation of 40.0 g of solid dry ice CO₂ is 29.3 kJ.

One mole of CO₂ has a mass of 44.0095 g.

Calculate the number of moles  n in 40.0 g of CO₂ .

$n =\frac{40.0 g}{44.0095 g/mol} = 0.9089 mol$

Heat of sublimation is the amount of heat required by 1 mole of a substance to convert itself from solid state to a vapor state at constant temperature and pressure.

1 mole of CO₂ requires 32.3 kJ of energy to sublimate.

Therefore, the heat required to sublimate 0.9089 mol of CO₂ is given by,

$Q = (32.3 kJ/mol)(0.9089 mol) =29.3 kJ$

Thus, the heat required to sublimate 40.0 g of CO₂ is 29.3 kJ.