How many grams of calcium carbonate, CaCO3, do you need in an antacid tablet to neutralize 20 mL of stomach acid? (stomach acid is 0.1 M HCl. There are 3.65g of HCl in 1L of stomach acid or 1g of HCl in 274g of stomach acid).

Answer 1

You have more information in the problem than you need.
Write the equation.
CaCO3 + 2HCl ==> CaCl2 + CO2
mols HCl = M x L = 0.1M x 0.020 L = ?
mols CaCO3 = 1/2 that (from the coefficients in the balanced equation).
Then grams CaCO3 = mols CaCO3 x molar mass CaCO3.

Answer 2

I didn't furnish the exact equation but it doesn't change anything in my answer.
CaCO3 + 2HCl ==> CaCl2 + CO2 + H2O

Answer 3

20ml solution (3.65/1000ml)(1mol hcl/36.4527gHcl)(1mol CaCo3/2molHCl) (100.0872 g CaCo3/1 mol CaCo3)= 0.1002g CaCo3