Question

How many hydrogen ions are in 1 liter of stomach acid? (Hint: Avogadro’s number). Show your work and remember to put your answer in regular number form (NOT scientific notation).

Answer 1

96,532,000,000,000,000,000,000 ions.

Step-by-step explanation:

• Assume the highest concentration of HCl in the stomach (160 mmol/L) that is in the canaliculi.

• This means that 1.0 L of the stomach acid contains 0.160 mol.

• Every 1.0 mole of HCl contains Avogadro’s number of molecules (6.022 x 10²³) molecules.

• Every 1.0 molecule of HCl contains 1.0 H⁺ ion.

Using cross multiplication:

1.0 mole of HCl → 6.022 x 10²³ H⁺ ions.

0.160 mole of HCl → ??? H⁺ ions.

∴ The no. of H⁺ ions in 1 liter of stomach acid = (6.022 x 10²³ H⁺ ions)(0.160 mole of HCl) / (1.0 mole of HCl) = 9.6352 x 10²² ions = 96,532,000,000,000,000,000,000 ions.