Question

what is the molar concentration of 2-methylbutanol in its neat solution?

Answer 1

The molecular formula of 2-methylbutanol is C₅H₁₂O

Molar mass of C₅H₁₂O = (5xAt.mass of C ) + (12 x At.mass of H ) + At.mass of O

                                  = (5x12)+(12x1)+ 16

                                  = 88 g/mol

We know that the density of C₅H₁₂O is , d = 0.809 g / mL

                                                              = 0.809 kg/L

So 1 L of the solution weighs 0.809 kg = 809 g
Therefore the number of moles of C₅H₁₂O in 1L of the solution is , n = mass/molar mass

                                                                                                  = 809 g / 88 (g/mol)

                                                                                                  = 9.193 mol
Therefore the concentration of C₅H₁₂O is , M = number of moles / volume of solution in L

                                                                 = 9.193 mol / 1L

                                                                 = 9.193 M

Therefore the molar concentration of 2-methylbutanol in its neat solution is 9.193 M