---

Question 1:

The pH scale measures the:

A) Concentration of hydrogen ions (H+)
B) Concentration of hydroxide ions (OH-)
C) Concentration of both hydrogen and hydroxide ions
D) pH stands for "pure hydrogen"

Show Answer

Explanation: The correct answer is A) Concentration of hydrogen ions (H+). The pH scale measures the concentration of hydrogen ions (H+) in a solution. It is a logarithmic scale that ranges from 0 to 14, with 7 being neutral, values less than 7 indicating acidity, and values greater than 7 indicating alkalinity or basicity.

---

Question 2:

A solution with a pH of 3 is considered:

A) Acidic
B) Neutral
C) Basic
D) Invalid pH value

Show Answer

Explanation: The correct answer is A) Acidic. A solution with a pH of 3 is considered acidic. Solutions with pH values less than 7 are acidic, with lower pH values indicating higher acidity.

---

Question 3:

The pH of a neutral solution is:

A) 0
B) 7
C) 14
D) It can vary

Show Answer

Explanation: The correct answer is B) 7. The pH of a neutral solution is 7. A neutral solution has an equal concentration of hydrogen ions (H+) and hydroxide ions (OH-) resulting in a balanced pH value of 7.

---

Question 4:

A solution with a pH of 9 is considered:

A) Acidic
B) Neutral
C) Basic
D) Invalid pH value

Show Answer

Explanation: The correct answer is C) Basic. A solution with a pH of 9 is considered basic. Solutions with pH values greater than 7 are basic, with higher pH values indicating higher basicity.

---

Question 5:

The pH of a solution can be calculated using the:

A) Concentration of hydroxide ions (OH-)
B) Concentration of both hydrogen and hydroxide ions
C) Ionization constant (Ka)
D) Concentration of hydrogen ions (H+)

Show Answer

Explanation: The correct answer is D) Concentration of hydrogen ions (H+). The pH of a solution can be calculated using the concentration of hydrogen ions (H+). pH is defined as the negative logarithm (base 10) of the hydrogen ion concentration, with the formula: pH = -log[H+].