Chemistry - Thermodynamics - I Question with Solution | TestHub

Find the moles of benzene: $Moles=\frac{Givenmass}{Molarmass}=\frac{7.8g}{78g/mol}=0.1mol$

Calculate total heat required ($Q$): $Q=Moles\times \Delta H_{vap}=0.1\times 30.84kJ=3.084kJ=3084J$

Formulate electrical energy supplied: $Energy=V\times I\times t=12V\times 0.5A\times t=6t$

Equate energy and solve for time ($t$): $6t=3084⟹t=\frac{3084}{6}=514seconds$