Question

are asic. If pH = 7, the solution is neutral. Questions: 4. The [H,0") of Coca-Cola is 3.2x10 What is its pH? Is it acidic or basic? 5. What is the [H90') of a tomato juice that has a pH of 4.1? Is it acidic or basic? 6. The pH of blood is 7.4, and the pH of milk is 6.4. Calculate the [H,0") for each solution. Compare these two numbers. What does this tell you about the pH scale? 7. Milk of Magnesia is an antacid used to neutralize stomach juices which have become too acidic. It has a pH of 10.5. What is the [H,O*]? What is the (OH)? Focus

Answer 1

pH is defined as:-

pH = -log([H30+1)

If, pH > 7, basic solution, pH < 7, acidic solution and pH = 7 neutral solution.

4.

H30+1 = 3.2 x 10-3

SO,

pH = -log(3.2 x 10-3) = 2.49

Since, pH < 7, coca-cola is acidic.

5.

pH of tomato juice = 4.1

SO,

4.1 = -log([H3O+]) 10-4.1 = H3071 So, [H3O+] = 7.94 x 10-5 M

pH < 7, tomato juice is acidic.

6.

pH of blodd is 7.4

7.4 = -log([H3O+]) 10-7.4 = [H3071 So, [H3O+] = 3.98 x 10-8 M

pH of milk is 6.4

6.4 = -log([H3O+]) 10-6.4 = (H3071 So, [H3O+] = 3.98 x 10-7 M

The concentration of hydronium ions in milk is more than the concentration of hydronium ions in blood. This is milk has lower pH than milk. pH scale is a scale which runs from 0 to 14. Milk will be placed in acidic medium and blood near neutral medium.

7.

pH of milk of magnesia = 10.5

10.5 = -log([H3O+]) 10-10.5 = [H3071 So, [H30+1 = 3.16 x 10-11 M

Also,

[H3O+][OH-] = 10-14 3.16 x 10-11 x [OH-] = 10-14

10-14 OH) = 316 X 10-11 10-1 M = 3.1 x 10-4 M