Which of the following is the normal potassium (K+) concentration in the blood?

The normal potassium concentration in the blood is recognized as being between 3.5 to 5.0 mEq/L. This range is crucial for various physiological functions, including nerve impulse transmission, muscle contraction, and maintaining overall fluid and electrolyte balance in the body. Potassium is an essential electrolyte, and deviations from this normal range can lead to significant clinical implications, such as arrhythmias or muscle weakness.

The specific range of 3.5 to 5.0 mEq/L is established based on extensive clinical research and laboratory data, making it the standard reference for evaluating potassium levels in patients. Maintaining potassium within this normal range is vital for optimal cellular function and health.