Posted by Ralph on .
Calculate and compare the mass of the reactants with the mass of the products for each equation.
a)2KClO3 (s) ==> 2KCl(s) + 3O2 (g)
b)4NH3(g) + 6NO(g) ==> 5N2(g) + 6H2O(g)
c)4K(s) + O2(g) ==> 2K2O(s)
Show that each balanced equation obeys the law of conservation of mass.

Chemistry 
DrBob222,
Calculate molar masses and show that they add up on both sides. For example, the first one.
KClO3 is 122.549 and 2 moles would be
2 x 122.549 = 245.098.
On the right we have
2 x 74.551 = 149.102 for 2KCl
3 x 31.9988 = 95.9964
149.102+95.9964 = 245.098
so the product decomposes but we didn't lose anything. The second one is done the same way.