Which statement correctly matches the normal ranges for the electrolytes listed?

Which statement correctly matches the normal ranges for the electrolytes listed?

• A. Potassium normal range is 3.5–5.0 mEq/L.
• B. Calcium total range is 8.0–9.0 mg/dL.
• C. Magnesium normal range is 2.0–3.0 mg/dL.
• D. Phosphate normal range is 1.0–2.0 mg/dL.

Answer: (A)

Understanding electrolyte reference ranges helps you interpret lab results accurately. Potassium normally ranges from 3.5 to 5.0 mEq/L, and this window is the standard used to identify hypo- or hyperkalemia and their potential cardiac effects. Calcium total is typically about 8.5–10.5 mg/dL, so a range of 8.0–9.0 mg/dL would not reflect the upper end of normal that many labs report. Magnesium normal serum is around 1.7–2.2 mg/dL; a 2.0–3.0 mg/dL range would exceed typical lower values and miss some normal results. Phosphate is normally about 2.5–4.5 mg/dL; a range of 1.0–2.0 mg/dL is too low to be considered normal. Therefore, the statement that potassium normal range is 3.5–5.0 mEq/L aligns with standard reference values.

Understanding electrolyte reference ranges helps you interpret lab results accurately. Potassium normally ranges from 3.5 to 5.0 mEq/L, and this window is the standard used to identify hypo- or hyperkalemia and their potential cardiac effects. Calcium total is typically about 8.5–10.5 mg/dL, so a range of 8.0–9.0 mg/dL would not reflect the upper end of normal that many labs report. Magnesium normal serum is around 1.7–2.2 mg/dL; a 2.0–3.0 mg/dL range would exceed typical lower values and miss some normal results. Phosphate is normally about 2.5–4.5 mg/dL; a range of 1.0–2.0 mg/dL is too low to be considered normal. Therefore, the statement that potassium normal range is 3.5–5.0 mEq/L aligns with standard reference values.