Question

before the introduction of chlorofluorocarbons, sulfur dioxide (entha;py of vapourization, 6.00 kcal/mol) was used in household refrigrators. What mass of SO2 must be evoparated o remove as much heat as evaporation of 1.00 kg of CCl2F2(enthalpy of vapourization is 17.4 kJ/mol)?
The vapourition reactions for SO2 and CCl2F2 re SO2 (i) ? SO2 and CCl2F(i) ? CCl2F2(g), respectively

Answer 1

Answer: 367 grams

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to the molecular mass and contains avogadro's number $6.023\times 10^{23}$ of particles.

Enthalpy of vaporization is the amount of heat released when 1 mole of substance is converted from liquid to gaseous state.

Given : Enthalpy of vapourization of $CCl_2F_2$ = 17.4 kJ/mol

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

$\text{Number of moles of}CCl_2F_2=\frac{1000g}{121g/mol}=8.3moles$

1 mole of $CCl_2F_2$ produces heat = 17.4 kJ

8.3 moles of $CCl_2F_2$ produces heat = $\frac{17.4}{1}\times 8.3=144 kJ$

Given : Enthalpy of vapourization of $SO_2$ = 6.0 kcal/mol = $6\times 4.184=25.104kJ$   (1kcal=4.184kJ)

25.104 kJ heat is produced by = 1 mole of $SO_2$

144 kJ  heat is produced by = $\frac{1}{25.104}\times 144=5.73mole$ of $SO_2$

Mass of $SO_2=moles\times {\text {molar mass}}=5.73\times 64=367g$

Thus 367 grams  of $SO_2$ must be evoparated o remove as much heat as evaporation of 1.00 kg of $CCl_2F_2$