Question

5. What is the molar mass of ethanol (C2H5OH)?

Answer 1

D) 46.07 g/mol

The molar mass is given by the sum of the atomic masses of the component elements of the substance.

In our case, the substance is ethanol or C₂H₅OH.

$A_C=12.011$

$A_H=1.0079$

$A_O=15.9994$

$\mathcal M_{C_2H_5OH} = 2 \times A_C + 6 \times A_H + A_O = 2 \times 12.011 + 6 \times 1.00079+ 15.999 4= 24.022 + 6.0474 + 15.9994= 46.069≈ \boxed{46.07 \dfrac{g}{mol}}$