How many grams is needed to react

1) how many grams of the primary standard sodium carbonate, Na2CO3 (mm= 105.99g/mol) is needed to react with 15 ml of 0.20 M HCl?

2)

moles HCl = M HCl x L HCl = (0.20)(0.015) = 0.0030 moles HCl

Na2CO3 + 2HCl ==> H2O + CO2 + 2NaCl

1 mole of Na2CO3 reacts with 2 moles of HCl.

0.0030 moles HCl x (1 mole Na2CO3 / 2 moles HCl) = 0.0015 moles Na2CO3

0.0015 moles Na2CO3 x (105.99 g Na2CO3 / 1 mole Na2CO3) = 0.16 g Na2CO3

one gram