Ph and molar concentration of hydrogen ion

Question

Assignment:

Q1. Given the molar concentration of hydrogen ion [H⁺] = 6.2 x 10 ^-7, calculate the concentration of hydroxide ion.

Q2. Given the molar concentration of hydroxide ion [OH ^-] = 4.6 X 10 ^-13, calculate the concentration of hydrogen ion.

Q3. In 1 mL of water there are 3 X 10²² molecules of H₂O. How many hydrogen ions are in 1 mL of water (Hint: In 1 billion water molecules, only 2 are ionized).

Q4. What is the pH of a 0.25 M NaOH solution?

Q5. A Rolaids tablet contains calcium carbonate, which neutralizes stomach acid. If 44.55 mL of 0.488 M hydrochloric acid is required to neutralize one tablet, how many milligrams of calcium carbonate are in a Rolaids tablet?

CaCO₃.(s) + 2 HCl(aq) ® CaCl₂(aq) + H₂O(l) + CO₂(g)

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