Nursing 354 Acid–Base Balance Practice
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. Which arterial blood gas (ABG) value is within the normal range for arterial
pH?
A. 7.20
B. 7.30
C. 7.40
D. 7.55
Answer: 7.40
Rationale: Normal arterial blood pH is 7.35–7.45. A pH below 7.35 indicates
acidemia, while a pH above 7.45 indicates alkalemia.
2. Which ABG value represents normal arterial carbon dioxide?
A. 20 mm Hg
B. 40 mm Hg
C. 55 mm Hg
D. 65 mm Hg
Answer: 40 mm Hg
,Rationale: Normal arterial partial pressure of carbon dioxide is 35–45 mm Hg.
Carbon dioxide acts as an acid because it combines with water to form carbonic
acid.
3. What is the normal arterial bicarbonate level?
A. 10–14 mEq/L
B. 15–18 mEq/L
C. 22–26 mEq/L
D. 30–35 mEq/L
Answer: 22–26 mEq/L
Rationale: Normal serum bicarbonate is approximately 22–26 mEq/L and
primarily reflects the metabolic component of acid–base balance.
4. A patient has a pH of 7.28. How should the nurse interpret this finding?
A. Normal acid–base balance
B. Alkalemia
C. Acidemia
D. Compensated alkalosis
Answer: Acidemia
Rationale: A pH below 7.35 indicates acidemia. The nurse should then examine
the carbon dioxide and bicarbonate values to determine the underlying disorder.
5. A patient has a pH of 7.50. Which condition does this finding indicate?
A. Acidemia
B. Alkalemia
C. Normal pH
D. Respiratory acidosis
,Answer: Alkalemia
Rationale: An arterial pH greater than 7.45 indicates alkalemia. The cause may
be respiratory or metabolic.
6. Which organ system provides the fastest compensation for acid–base
disturbances?
A. Kidneys
B. Lungs
C. Liver
D. Gastrointestinal system
Answer: Lungs
Rationale: The lungs can alter carbon dioxide elimination within minutes. The
kidneys provide slower but more sustained compensation.
7. Which laboratory value primarily represents the respiratory component of
acid–base balance?
A. Bicarbonate
B. Sodium
C. Carbon dioxide
D. Potassium
Answer: Carbon dioxide
Rationale: Arterial carbon dioxide reflects the respiratory component of acid–
base regulation because ventilation controls carbon dioxide elimination.
8. Which laboratory value primarily represents the metabolic component of
acid–base balance?
, A. Bicarbonate
B. Carbon dioxide
C. Oxygen
D. Chloride
Answer: Bicarbonate
Rationale: Bicarbonate is the primary metabolic component evaluated when
interpreting acid–base balance. The kidneys regulate bicarbonate levels.
9. A patient has a pH of 7.25, carbon dioxide of 55 mm Hg, and bicarbonate of 24
mEq/L. Which disorder is present?
A. Metabolic acidosis
B. Respiratory acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
Answer: Respiratory acidosis
Rationale: The pH is low and the carbon dioxide is elevated, indicating a primary
respiratory acidosis. The bicarbonate remains within the normal range,
suggesting little or no metabolic compensation.
10. A patient has a pH of 7.52, carbon dioxide of 30 mm Hg, and bicarbonate of
24 mEq/L. Which disorder is present?
A. Respiratory acidosis
B. Metabolic acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
Answer: Respiratory alkalosis
Rationale: The elevated pH indicates alkalemia, while the low carbon dioxide
indicates excessive carbon dioxide loss from increased ventilation.
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. Which arterial blood gas (ABG) value is within the normal range for arterial
pH?
A. 7.20
B. 7.30
C. 7.40
D. 7.55
Answer: 7.40
Rationale: Normal arterial blood pH is 7.35–7.45. A pH below 7.35 indicates
acidemia, while a pH above 7.45 indicates alkalemia.
2. Which ABG value represents normal arterial carbon dioxide?
A. 20 mm Hg
B. 40 mm Hg
C. 55 mm Hg
D. 65 mm Hg
Answer: 40 mm Hg
,Rationale: Normal arterial partial pressure of carbon dioxide is 35–45 mm Hg.
Carbon dioxide acts as an acid because it combines with water to form carbonic
acid.
3. What is the normal arterial bicarbonate level?
A. 10–14 mEq/L
B. 15–18 mEq/L
C. 22–26 mEq/L
D. 30–35 mEq/L
Answer: 22–26 mEq/L
Rationale: Normal serum bicarbonate is approximately 22–26 mEq/L and
primarily reflects the metabolic component of acid–base balance.
4. A patient has a pH of 7.28. How should the nurse interpret this finding?
A. Normal acid–base balance
B. Alkalemia
C. Acidemia
D. Compensated alkalosis
Answer: Acidemia
Rationale: A pH below 7.35 indicates acidemia. The nurse should then examine
the carbon dioxide and bicarbonate values to determine the underlying disorder.
5. A patient has a pH of 7.50. Which condition does this finding indicate?
A. Acidemia
B. Alkalemia
C. Normal pH
D. Respiratory acidosis
,Answer: Alkalemia
Rationale: An arterial pH greater than 7.45 indicates alkalemia. The cause may
be respiratory or metabolic.
6. Which organ system provides the fastest compensation for acid–base
disturbances?
A. Kidneys
B. Lungs
C. Liver
D. Gastrointestinal system
Answer: Lungs
Rationale: The lungs can alter carbon dioxide elimination within minutes. The
kidneys provide slower but more sustained compensation.
7. Which laboratory value primarily represents the respiratory component of
acid–base balance?
A. Bicarbonate
B. Sodium
C. Carbon dioxide
D. Potassium
Answer: Carbon dioxide
Rationale: Arterial carbon dioxide reflects the respiratory component of acid–
base regulation because ventilation controls carbon dioxide elimination.
8. Which laboratory value primarily represents the metabolic component of
acid–base balance?
, A. Bicarbonate
B. Carbon dioxide
C. Oxygen
D. Chloride
Answer: Bicarbonate
Rationale: Bicarbonate is the primary metabolic component evaluated when
interpreting acid–base balance. The kidneys regulate bicarbonate levels.
9. A patient has a pH of 7.25, carbon dioxide of 55 mm Hg, and bicarbonate of 24
mEq/L. Which disorder is present?
A. Metabolic acidosis
B. Respiratory acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
Answer: Respiratory acidosis
Rationale: The pH is low and the carbon dioxide is elevated, indicating a primary
respiratory acidosis. The bicarbonate remains within the normal range,
suggesting little or no metabolic compensation.
10. A patient has a pH of 7.52, carbon dioxide of 30 mm Hg, and bicarbonate of
24 mEq/L. Which disorder is present?
A. Respiratory acidosis
B. Metabolic acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
Answer: Respiratory alkalosis
Rationale: The elevated pH indicates alkalemia, while the low carbon dioxide
indicates excessive carbon dioxide loss from increased ventilation.
