Question #e0d9c

1 Answer
Mar 1, 2017

Answer:

#"1.19090412854 gram of" O_2#

Explanation:

1 mole of MgO has 1 mole of Mg and 1 mole #O_2#

amount of Mg in 3 grams of MgO

Molar mass of MgO = 24.305mol + 15.999mol = 40.304mol

Moles in 3grams = #"3g"/"40.304mol/gram" = 0.07443429932mol#

Mole Ratio of O to MgO

1mol : 1mol

Therefore amount of oxygen in MgO

0.07443429932mol : 0.07443429932mol

Therefore there is 0.07443429932 moles of #O_2#

Weight of 0.07443429932moles of #O_2 # =

#"0.07443429932moles" * "15.9994mol/gram" = "1.19090412854 gram of" O_2#