Strong electrolytes are those which:

Options

A. conduct electricity
B. dissolve readily in water
C. dissolve into ions at high dilution
D. completely dissociation into ions

Answer

**Step-by-Step Solution:**

1. **Understanding Strong Electrolytes**: Strong electrolytes are substances that completely dissociate into ions when they are dissolved in water. This means that when a strong electrolyte is added to water, it breaks apart into its constituent ions.

2. **Dissociation Example**: For instance, if we take a strong electrolyte like sodium chloride (NaCl), it dissociates in water as follows:
\[ \text{NaCl} \rightarrow \text{Na}^+ + \text{Cl}^- \]
This shows that NaCl completely dissociates into sodium ions (Na⁺) and chloride ions (Cl⁻).

3. **Conduction of Electricity**: The presence of these free ions in solution allows the solution to conduct electricity. Electrical conduction in solutions occurs due to the movement of these charged particles (ions).

4. **Analyzing Given Options**:
- **Option A**: Strong electrolytes conduct electricity. This is true because they produce free ions in solution.
- **Option B**: Strong electrolytes dissolve readily in water. This is also true as they are soluble and dissociate completely.
- **Option C**: Strong electrolytes dissolve into ions at high dilution. This is incorrect; this characteristic applies to weak electrolytes, which only partially dissociate at low concentrations.
- **Option D**: Strong electrolytes completely dissociate into ions. This is true, as we established earlier.

5. **Conclusion**: The correct options that describe strong electrolytes are A (conduct electricity), B (dissolve readily in water), and D (completely dissociate into ions). Therefore, the answer includes options A, B, and D.

**Final Answer**: Strong electrolytes are those which conduct electricity, dissolve readily in water, and completely dissociate into ions.

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