I would say it is the amount of mass, but double check
The density of an object is mass / volume. These units are unusual but since you are reporting your answer in kg/L, the actual conversion is unnecessary
d = m/V
d = 7.2 kg / 9 L
d = 0.8 kg / L
CO2. An ionic compound is a metal and a nonmetal.
Answer:
The same 45.98 g of NaCl will be produced since 2 moles of Na will react with 2 moles of NaCl. Hence the stoichiometric coefficient will be in a ratio of 1:1