Question

the mass of caco3 required to react completely with 20 ml of 1.0 M HCL as per the reaction is?

Answer 1

1 mole of CaCO3 reacts with 2 moles of HCl from the equation.

We have 1M 20 mL HCl i.e. no of moles of HCl is : 20/1000 = 0.02

Thus no of moles required to completely consume 0.02 moles of HCl = 0.02/2 = 0.01

Mass of CaCO3 = no of moles * molar mass = 0.01*100 = 1g

hope this helps.