a. 10.5g of zinc trioxocarbonate (iv) was heated strongly to a constant mass, giving zinc oxide and carbon (iv) oxide; and the residue was treated with excess hydrochloric acid. i. 11.
Write equations for the above processes. Calculate the mass of zinc chloride that would be obtained.
b. Find the mass of sodium trioxocarbonate (iv) needed to give 11.2dm³ of carbon (iv) oxide at s.t.p. in this reaction.
Na₂CO + 2HCl(a) → 2NaCl(aq) + CO (E) + H₂Om
[2n=65, C-12, 0-16, H=1, Cl-35.5, Na-23, molar volume of gas at s.t.p.-22.4]
I must tell you that zinc triowhatever is not a correct name for anything.
Zinc carbonate is a perfectly good name for ZnCO3.
ZnCO3 + heat ==> ZnO + CO2
ZnO + 2HCl ==> ZnCl2 + H2O
moles ZnCO3 = grams/molar mass = 10.5/125 = 0.084
Convert mols ZnCO3 to mols ZnCl2 by using the coefficients in the balanced equation like this.
0.084 moles ZnCO3 x (1 mol ZnO/1 mol ZnCO3) x (1 mol ZnCl2/1 mol ZnO) = 0.084 moles ZnCl2.
Grams ZnCl2 = moles ZnCl2 x molar mass ZnCl2 = ?
The b part makes no sense. Im guessing you meant to ask for mass ZnCO3 but you wrote 2n instead of Zn and you wrote an equation with Na2CO3 and not ZnCO3.