The daily output of stomach acid (gastric juice) is 1000 to 2000 mL. Prior to a meal, stomach acid (HCl) typically has a pH of 1.39.

Question

A) What is the [H3O+] of stomach acid?

B)One chewable tablet of the antacid Maalox contains 600. mg of CaCO3. Enter the neutralization equation.

C)Given that one chewable tablet of the antacid Maalox contains 600. mg of CaCO3, calculate the milliliters of stomach acid neutralized by two tablets of Maalox.

D)The antacid milk of magnesia contains 400. mg of Mg(OH)2 per teaspoon. Enter the neutralization equation.

E)Given that the antacid milk of magnesia contains 400 mg of Mg(OH)_2 

per teaspoon, calculate the number of milliliters of stomach acid that are neutralized by 1 tablespoon of milk of magnesia. (1 tablespoon = 3 teaspoons.)

Answer 1

There is a very lot here to answer, so I will set most of it up for you, but hope that you will be able to complete the answer.

A. From pH = 1.39 we can find [H⁺] b/c pH = -log [H⁺]. Thus, [H⁺] = 1x10^-1.39 = 4.07x10^-2 M

B. CaCO₃ + 2HCl ==> CaCl₂ + 2H₂O ... balanced equation for neutralization

C. 2 tabs x 600 mg/tab x 1 g/1000 mg x 1 mol CaCO3/100 g x 2 mol HCl/mol CaCO3 x 1 L/4.07x10^-2 mol HCl x 1000 ml/L = mls HCl

D. Mg(OH)2 + 2HCl ==> MgCl2 + 2H2O ... balanced equation for neutralization

E. 1 Tbl x 3 tsp/Tbl x 400 mg Mg(OH)2/tsp x 1 g/1000 mg x 1 mol Mg(OH)2/58.3g x 2 mol HCl/mol Mg(OH)2 x 1 L HCl/4.07x10^-2 mol HCl x 1000 ml/L = mls HCl