Question

1 gram of a carbonate (m2co3 ) on treatment with excess hcl produces 0.01186 mole of co2 . the molar mass of m2co3 in g mol−1 is :

Answer 1

The equation for the above reaction is as follows:-

M2CO3 + 2HCl-> 2MCl+CO2+2H2O

This shows that ,
1 mole of CO2 is produced from -> 1 mole of M2CO3

Given that,
0.01186 mole of CO2 needs -> 1g of M2CO3

1 mole of CO2 needs -> (1g/0.01186mole)*1 mole = 84.31g

Hence, 84.31g being the mass of 1 mole of the carbonate is its molar mass.
Ans:- 84.31 g/mole

Answer 2

M²CO³ +2HCL--> CO²+2MCl+H²O

Moles of M²CO³= Moles of CO² produced

Moles of M²CO³ = w/molar mass

= 0.01186

So, molar mass= 84.3 g mol^-1