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 = <span>24.31 + (2 x 35.45) = 95.21 g/mol
</span><span>340 g MgCl2 ( 1 mol / 95.21 g ) = 3.57 mol MgCl2
Hope this answers the question. Have a nice day.</span>