Mole is the ratio of the mass to the molar mass of the substance and its unit is mol. The moles of isopropanol in the sample are 1. 31 moles.
Moles are the unit of measurement of the smallest entity of atoms, molecules, and compounds.
Given,
Mass of isopropanol (m) = 78. 6 g
Molar mass of isopropanol = 60. 1 g/mol
Moles of isopropanol is calculated as:
[tex]\begin{aligned} \rm moles (n) &= \rm \dfrac{mass}{molar \; mass}\\\\&= \dfrac{78.6}{60.1}\\\\&= 1.31\;\rm moles\end{aligned}[/tex]
Therefore, moles of isopropanol are option b. 1.31 moles.
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