A reaction where one becomes two
2H202 --> 2H2O + O2
The equation to calculate Density is Mass / Volume. You are given that the density is 5.45 and the mass is 65; 5.45 = 65 / v. So v = 65 / 5.45; v = 11.93 mL (or if you want your answer to consider significant figures, v = 12 mL).
Answer: Mass of
produced in this reaction was 6.56 grams
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

Mass or reactants = Mass of
+ mass of
= 16.00 + 64.80 = 80.80 g
Mass of products = mass of aqueous solution + mass of
+ = 74.24 + x g
Mass or reactants = Mass of products
80.80 g = 74.24 + x g
x = 6.56 g
Thus mass of
produced in this reaction was 6.56 grams
Answer: 55.84L
Explanation: Please see attachment for explanation.