Question #038ae

1 Answer
Jan 22, 2018

54.41 grams.

Explanation:

In general, the mass of a substance can be found from the number of moles by:

"mass" = "moles" xx "molar mass"

For "MgO", the molar mass of the molecule can be found by adding up the molar masses of its constituent atoms. That is, (values taken from Google)

"molar mass"("MgO") = "molar mass"("Mg") + "molar mass"("O")

= "24.31 g.mol" + "16.00 g/mol"

"= 40.31 g/mol"

Or, the molar mass of "MgO" might often be given to you. Either way,

"mass" = "moles" xx "molar mass"

= "1.350 moles" xx "40.31 g/mol"

"= 54.41 g" (rounded)