Practice electrolyte lab values and clinical interpretation with 25 questions covering sodium, potassium, calcium, magnesium, chloride, fluid balance, kidney function, and cardiac rhythm connections.
This quiz is designed for nursing students, TEAS learners, healthcare students, and anyone reviewing common lab values.
Electrolytes help regulate fluid balance, nerve signaling, muscle contraction, acid-base balance, and heart rhythm. When electrolyte levels are too high or too low, patients may show changes in vital signs, mental status, muscle function, or cardiac rhythm.
Potassium is one of the most important electrolytes to recognize because abnormal potassium levels can affect cardiac rhythm.
| Electrolyte | Common Normal Range | Why It Matters |
|---|---|---|
| Sodium | 135–145 mEq/L | Fluid balance, neurologic status, hydration, and osmotic balance. |
| Potassium | 3.5–5.0 mEq/L | Cardiac rhythm, muscle function, nerve signaling, and safety monitoring. |
| Calcium | 8.5–10.5 mg/dL | Muscle contraction, bone health, nerve function, and cardiac activity. |
| Magnesium | 1.5–2.5 mEq/L | Neuromuscular function, cardiac rhythm support, and electrolyte balance. |
| Chloride | 96–106 mEq/L | Fluid balance and acid-base support. |
Do not only memorize the ranges. Learn what each electrolyte affects and what can happen when it is too high or too low.
Electrolytes, especially potassium, calcium, and magnesium, are closely connected to cardiac electrical activity. This is why electrolyte problems can show up on monitoring, rhythm strips, or EKG review.
If you are reviewing cardiac rhythm recognition, continue with the How to Read an EKG Guide and the EKG Practice Quiz.
The kidneys help regulate electrolyte levels by filtering blood, reabsorbing what the body needs, and removing excess substances in urine. When kidney function changes, electrolyte values may change too.
This is especially important with potassium. If the kidneys are not removing potassium well, potassium can build up and increase the risk of dangerous rhythm changes.
Review this connection in How the Kidneys Work.
Electrolytes connect directly to lab values, vital signs, kidney function, ABG interpretation, and EKG rhythm recognition.
Keep building your healthcare fundamentals by reviewing connected topics.