Question

how many moles of chloride ions are there in 0.0750 of mgcl2

Answer 1

0.0750 g MgCl2) / (95.2115 g MgCl2/mol) x (2 mol Cl{-} / 1 mol MgCl2) = 
1.58 x 10^-3 mol

Answer 2

Explanation:

It is known that number of moles of a substance equals to the mass divided by molar mass.

As, molar mass of magnesium chloride is 95.211 g/mol. Therefore, no. of moles of $MgCl_{2}$ present in 0.0750 g are as follows.

                 No. of moles = $\frac{mass}{\text{molar mass}}$

                                       = $\frac{0.0750 g}{95.211 g/mol}$  

                                        = 0.00078 mol

Since, there are two chloride ions present in a molecule of $MgCl_{2}$. Therefore, moles of chloride ions present in it are as follows.

                         $2 \times 0.00078 mol$ = 0.0016 mol

Hence, we can conclude that there are 0.0016 mol of chloride ions present in 0.0750 g of $MgCl_{2}$.