How many oxygen atoms are represented by #MgSO_4 * 7H_2O#?

1 Answer
Dec 20, 2015

#11#

Explanation:

In #"MgSO"_4#, the number of oxygen atoms is represented by the subscript directly next to the #"O"#.

In #"7H"_2"O"#, the coefficient #7# can be multiplied throughout each element in the molecule.

#"MgS"color(red)("O"_4)rarr"4 O atoms"#

#color(red)("7")"H"_2color(red)("O")rarr"7 O atoms"#

There is a total of #4+7=11# oxygen atoms.