Zinc carbonate weighing 50 g was heated to a high temperature. Write the equation for the reaction.

Zinc carbonate weighing 50 g was heated to a high temperature. Write the equation for the reaction. Calculate the volume of gas that has evolved and its relative density in the air. Determine the mass of the solid residue and write the equation for the reactions of its interaction with sodium hydroxide, chloride acid, potassium carbonate and sulfur oxide

ZnCO3 = ZnO + CO2
n (ZnCO3) = 50 / 125.3 = 0.4 mol
n (CO2) = 0.4
v (co2) = 0.4 * 22.4 = 8.96 liters
M (co2) = 44
air density is 44/29 = 1.52
m (ZnO) = 0.4 * 81.3 = 32.52 g
ZnO + 2KOH + H2O = K2 (Zn (OH) 4)
ZnO + HCl = ZnCl2 + H2O
ZnO + Na2CO3 = Na2ZnO2 + CO2
ZnO + SO3 = ZnSO4