For the reaction #2HNO_3 + Mg(OH)_2 -> Mg(NO_3)_2 + 2H_2O#, how many grams of magnesium nitrate are produced from 8 moles of water?

1 Answer
Jun 2, 2018

#593.2 " g "Mg(NO_3)_2#

Explanation:

We can use stoichiometry to find the moles of #Mg(NO_3)_2# and then the respective grams of #Mg(NO_3)_2#.

If 8 moles of water are produced, we can find out how many moles of #Mg(NO_3)_2# are produced using this equation:

#(8 " "cancel("mol "H_2O))/1*(1 " mol " Mg(NO_3)_2)/(2" "cancel("mol "H_2O))=4" mol "Mg(NO_3)_2#

From here, we can use ratios to convert to the grams of #Mg(NO_3)_2#:

#(4 " "cancel("mol "Mg(NO_3)_2))/1*(148.3 " g " Mg(NO_3)_2)/(1 " "cancel("mol " Mg(NO_3)_2))=593.2 " g "Mg(NO_3)_2#

(You can get the molar mass of #Mg(NO_3)_2# by referencing a periodic table and summing the masses of each element in the compound.)