In basic chemistry, which of the following substances behaves as an electrolyte when dissolved in water?

Introduction / Context:
Electrolytes are substances that produce ions when dissolved in water and therefore conduct electricity in solution. Understanding which compounds are electrolytes is important in chemistry, biology, medicine, and many industrial processes. This question asks you to identify which among some common acids and salts act as electrolytes in aqueous solution. Recognising strong acids and ionic salts as electrolytes is a key part of introductory chemistry and helps in predicting conductivity and reaction behaviour in solutions.

Given Data / Assumptions:
- The substances listed are hydrochloric acid HCl, sodium chloride NaCl, and hydrobromic acid HBr. - The question asks which of these behaves as an electrolyte in water. - We assume normal dilute aqueous solutions at room temperature.

Concept / Approach:
An electrolyte is defined as a substance that dissociates into ions in water and allows the solution to conduct electric current. Strong acids such as HCl and HBr ionize almost completely in water to produce hydrogen ions and their respective anions. Ionic salts such as NaCl dissociate into positive and negative ions as well. Because all these substances form free ions, they all behave as electrolytes. Strong electrolytes, in particular, dissociate almost completely, giving high conductivity compared to weak electrolytes that ionize only partially.

Step-by-Step Solution:
Step 1: Consider HCl in water. Hydrochloric acid dissociates fully into H plus and Cl minus ions, so an aqueous solution of HCl conducts electricity well. Step 2: Consider NaCl in water. Sodium chloride is an ionic compound made of Na plus and Cl minus ions. In water it dissociates into these ions, so it is also an electrolyte. Step 3: Consider HBr in water. Hydrobromic acid behaves similarly to HCl and dissociates almost completely into H plus and Br minus ions, making it a strong electrolyte. Step 4: Since all three substances form ions in aqueous solution and conduct electricity, they all qualify as electrolytes, so the best answer is All of the above.

Verification / Alternative check:
To verify, imagine placing electrodes into each aqueous solution and connecting them to a simple circuit. The solutions of HCl, NaCl, and HBr will all allow current to pass through because of the presence of mobile ions. This is the experimental test for an electrolyte. Textbooks on general chemistry also list strong acids and most soluble ionic salts as strong electrolytes, confirming that each individual substance given in the options is indeed an electrolyte.

Why Other Options Are Wrong:
Option A (Hydrochloric acid HCl) is an electrolyte, but choosing only this option would ignore the fact that the other listed substances are electrolytes as well. Option B (Sodium chloride NaCl) is also an electrolyte, but again it is not the only one among the options. Option C (Hydrobromic acid HBr) is a strong acid and thus an electrolyte, but the question asks which compound is an electrolyte among all listed, so the single choice is incomplete.

Common Pitfalls:
Learners sometimes think that only acids are electrolytes and overlook ionic salts such as NaCl. Another common mistake is to assume that a compound must contain hydrogen to act as an electrolyte, which is not true. There is also confusion between weak and strong electrolytes, but the key point here is that all the listed substances do produce ions in solution. Always remember that any substance that generates mobile ions in water can conduct electricity and is therefore an electrolyte.

Final Answer:
The correct answer is: All of the above.