Question

A 18.5 g sample of a mixture of magnesium carbonate and calcium carbonate is treated with excess HCl. The resulting reaction produces 5.23 L of carbon dioxide gas at 28 °C and 753 torr. Write a balanced chemical equation for the reaction that takes place between magnesium carbonate and HCl. Include physical states. chemical reaction: Write a balanced chemical equation for the reaction that takes place between calcium carbonate and HCl. Include physical states. chemical reaction: Calculate the total number of moles of carbon dioxide that forms from these reactions. moles of carbon dioxide: mol Assuming the reactions are complete, calculate the precentage by mass of magnesium carbonate and calcium carbonate in the mixture. magnesium carbonate: calcium carbonate:

Answer 1

a) balance chemical equation bietween myco, and excess HCL- Mg cong (5) + 2 HCl (aq) mg Cl; (aq) + M20(4) U + 20,19) b) balance chemical equation between cach, and excess Hd :- CaCO₃(s) + 2HCl(aq) Cach, (aq) + H₂0 (1) in + co₂ ↑ (g) MgCO3 + CaCO₃ + 4H0 Mg Cl₂ + CaCl2 + 2H2O + 20, Now, Total weight of sample = 18.5 g volume of sesulting reaction = 51234 poresswie of system = 753 tonn = 753 afm el atm = 760 tonn] =0.990 atm and T = 28 € = (28+ 273 k = 300k Now, assuming coz behares as ideal gas we are applying the ideal gas Lould we get PV = nRT (n=no, of mole of A co produced) 0.990% 5.23 - 1X0.0824 X 301 = 0.990 x 5.23 TEA 0.0821 x 301 = 0.209 mol no. of moles of con produced = 0-209 most .
hi
d) Assume a g cacoz and (18.5-x) g has taken for this reaction. Molecular weight of Calog = 100 g and Molecular weight of Mg CO₂ = 84 g ::: X 9 Cacoz = mol CaCO3 100 and 1815 - 18-5-x mol MgCO3 each on, from balanced equation we see that 1 mol mg coz and 1 mol CaCO3 give 1 mol CO2 each Total a mol of cog evolved from Mg Co, and Cacoz = (imo + 18*2) & previously we get , mol of co, evolved = 0.209 X "1815-X . 10084 0.209 16 · => 842 + 1850-100% = 0.209 8400 - 16x = -944 > x = 94.4 = 519 g Cacoz 4.5.9 g caco, and (18.5-519) = 12.6 g exemglaz was taken % of mass of caloz = 15 15 100)% = 31-89% and / of mass of MgCO3 = (1 2 1 x 100) %. = 68.11%.