Question

consider the thermochemical equation for the combustion of acetone (c₃h₆o), the main ingredient in nail polish remover. c₃h₆o(l) + 4o₂(g) → 3co₂(g) + 3h₂o(l) δᵣh° = -1790 kj mol⁻¹ part a if a bottle of nail polish remover contains 161 ml of acetone, how much heat is released by its complete combustion? the density of acetone is 0.788 g ml⁻¹. express your answer in kilojoules to three significant figures.

Explanation:

Step1: Calculate mass of acetone

$m=
ho V$, where $
ho = 0.788\ g/mL$ and $V = 161\ mL$. So $m=0.788\ g/mL\times161\ mL = 126.868\ g$.

Step2: Calculate molar mass of acetone ($C_3H_6O$)

$M=(3\times12.01 + 6\times1.01+16.00)\ g/mol=58.08\ g/mol$.

Step3: Calculate moles of acetone

$n=\frac{m}{M}=\frac{126.868\ g}{58.08\ g/mol}\approx2.184\ mol$.

Step4: Calculate heat released

From the thermochemical equation, $\Delta H = - 1790\ kJ/mol$. The heat released $q = n|\Delta H|$. So $q=2.184\ mol\times1790\ kJ/mol\approx3910\ kJ$.

Answer:

$3910$