Question

Determine the volume of hexane that contains 5.33 × 1022 molecules of hexane. The density of hexane is 0.6548 g/ml and its molar mass is 86.17 g/mol.

Answer 1

we are asked to find the volume of hexane. Density is mass per given volume.

1 mol of any substance is made of 6.022 x 10²³ units, these units could be atoms making up an element or molecules making up a compound.

the number of molecules in hexane has been given therefore we can find the number of moles of hexane

6.022 x 10²³ molecules make up - 1 mol

therefore 5.33 x 10²² molecules make - 1 / (6.022 x 10²³) x 5.33 x 10²²

                                                               = 0.0885 mol

since we know the molar mass and number of moles, mass of hexane can be calculated

mass of hexane = 86.17 g/mol x 0.0885 mol = 7.63 g

density has been given, therefore we can find the volume

volume = mass / density

volume = 7.63 g / 0.6548 g/ml = 11.7 ml

volume of hexane is 11.7 ml