Answer:
126.5g
Explanation:
n=<u>m</u><u> </u>
M
where n is moles
m is mass of substance
M is molar mass
molar mass of sodium is 23g/mol
m=nM
m=5.5(23)
m=126.5
X = Water (H2O) ; Y = Hydrogen ; Z = Oxygen
2(H2O) -------> 2H2 + O2
oxide of potassium or potassium oxide i believe.