Carbonic acid (H2CO3) is a weak diprotic acid withKa1=4.43�10?7 and Ka2=4.73�10?11. When sodiumbicarbonate (NaHCO3) is titrated with hydrochloric acid (HCl), itacts as a weak base according to the equation
NaHCO3(aq)+HCl(aq)?H2CO3(aq)+NaCl(aq)
1)What volume of 0.180M HCl is required for thecomplete neutralization of 1.50g of NaHCO3 (sodiumbicarbonate)?
2)What volume of 0.120M HCl is required for thecomplete neutralization of 1.10g of Na2CO3 (sodium carbonate)?
3)A sample of NaOH (sodium hydroxide) contains a small amount ofNa2CO3 (sodium carbonate). For titration to the phenolphthaleinendpoint, 0.160g of this sample requires 23.98 mL of 0.100M HCl. An additional 0.700 mL of 0.100 M HCl isrequired to reach the methyl orange endpoint. What is thepercentage of Na2CO3 by mass in the sample?
