Question

Sodium hydrogen carbonate NaHCO3 , also known as sodium bicarbonate or "baking soda", can be used to relieve acid indigestion. Acid indigestion is the burning sensation you get in your stomach when it contains too much hydrochloric acid HCl, which the stomach secretes to help digest food. Drinking a glass of water containing dissolved NaHCO3 neutralizes excess HCl through this reaction:

HCl (aq) + NaHCO3 (aq) → NaCl (aq) + H2O (l) + CO2 (g)

The CO2 gas produced is what makes you burp after drinking the solution.

Suppose the fluid in the stomach of a man suffering from indigestion can be considered to be 50.mL of a 0.067 M HCl solution. What mass of NaHCO3would he need to ingest to neutralize this much HCl ? Round your answer to 2 significant digits.

Answer 1

Solution- The reaction is

HCl(aq) + NaHCO3 (aq) → NaCl (aq) + H2O (l) + CO2 (g)

1 mole     1 mole

no of moles of HCl = molarity * volume in L

                            = 0.067*0.05 = 3.35*10^-3 moles

Now from balanced equation

1 mole of HCl react with 1 mole of NaHCO3

3.35*10^-3 mole of HCl react with 3.35*10^-3 moles of NaHCO3

mass of NaHCO3 = no of moles of NaHCO3 * molar mass

                         = 3.35*10^-3*84 = 0.2814gm

mass of NaHCO3 is 0.28 gm