Respuesta :

To calculate the amount of the compound in the units of grams, we need to first obtain for the molar mass of the compound. We calculate as follows:

MgCl2 = 24.31 + (2 x 35.45) = 95.21 g/mol

340 g MgCl2 ( 1 mol / 95.21 g ) = 3.57 mol MgCl2

Hope this answers the question. Have a nice day.

Explanation:

Moles is defined as mass divided by molar mass.

Mathematically,          Number of moles = \frac{mass}{molar mass}[/tex]

Therefore, it is given that mass is 340 g and molar mass of [tex]MgCl_{2}[/tex] is 95.211 g/mol.

Hence, calculate number of moles as follows.

                   Number of moles = [tex]\frac{mass}{molar mass}[/tex]

                                                 = [tex]\frac{340 g}{95.211 g/mol}[/tex]

                                                 = 3.57 mol

Thus, we can conclude that there are 3.57 moles of MgCl2 are there in 340 g of the compound.