First, we have to find the no. Of moles. For this purpose, we will use avagadro's number

1 mole = 6.023*10^23 molecules

Therefore, the number of moles are

(1 *10^23)/(6.023*10^23) = 0.166 moles

======

Formula mass of MgSiF6 :::: = 24 + 28 + 6*19

= 166g

ANSWER: 0.166 moles * 166g/mol

= 26.56g

1 mole = 6.023*10^23 molecules

Therefore, the number of moles are

(1 *10^23)/(6.023*10^23) = 0.166 moles

======

Formula mass of MgSiF6 :::: = 24 + 28 + 6*19

= 166g

ANSWER: 0.166 moles * 166g/mol

= 26.56g