pH and hydrogen ion concentration

Question 1

A strong acid solution has a hydrogen ion concentration of 0.0001 mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer 

Question 2

Solution X has pH 1 and solution Y has pH 4. How many times greater is the hydrogen ion concentration in X than in Y?

Answer 

Question 3

Ocean water's pH has fallen from about 8.2 to about 8.1 since the 1800s. Roughly how has the H⁺ concentration changed?

• A. it has increased 10 times
• B. it has increased by about 25–30 %
• C. it has not changed
• D. it has fallen by half

Question 4

A strong acid solution has a hydrogen ion concentration of 0.1 mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer 

Question 5

Solution X has pH 1 and solution Y has pH 3. How many times greater is the hydrogen ion concentration in X than in Y?

Answer 

Question 6

Which statement about "concentrated" and "strong" is correct?

• A. Strong acids are always concentrated
• B. They mean the same
• C. A weak acid can be concentrated, and a strong acid can be dilute
• D. Weak acids are always dilute

Question 7

A strong acid solution has a hydrogen ion concentration of 0.1 mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer 

Question 8

Solution X has pH 5 and solution Y has pH 8. How many times greater is the hydrogen ion concentration in X than in Y?

Answer 

Question 9

Ocean water's pH has fallen from about 8.2 to about 8.1 since the 1800s. Roughly how has the H⁺ concentration changed?

• A. it has fallen by half
• B. it has increased by about 25–30 %
• C. it has not changed
• D. it has increased 10 times

Question 10

A strong acid solution has a hydrogen ion concentration of 1 × 10⁻² mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer 

Question 11

Solution X has pH 5 and solution Y has pH 6. How many times greater is the hydrogen ion concentration in X than in Y?

Answer 

Question 12

Which statement about "concentrated" and "strong" is correct?

• A. Strong acids are always concentrated
• B. Weak acids are always dilute
• C. They mean the same
• D. A weak acid can be concentrated, and a strong acid can be dilute

Question 13

A strong acid solution has a hydrogen ion concentration of 1 × 10⁻² mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer 

Question 14

Solution X has pH 1 and solution Y has pH 3. How many times greater is the hydrogen ion concentration in X than in Y?

Answer 

Question 15

Which statement about "concentrated" and "strong" is correct?

• A. A weak acid can be concentrated, and a strong acid can be dilute
• B. Strong acids are always concentrated
• C. Weak acids are always dilute
• D. They mean the same

Question 16

A strong acid solution has a hydrogen ion concentration of 1 × 10⁻⁴ mol/dm³. What is its pH? (pH = −log₁₀[H⁺])

Answer