Final answer:
Lithium bromide (LiBr) is the strong electrolyte among the options listed as it is a soluble ionic compound that dissociates completely into ions in solution, making it a strong electrolyte.
Step-by-step explanation:
The question asks which of the given substances is a strong electrolyte. Strong electrolytes are substances that dissociate almost 100% into ions when dissolved in water and include solutes that are either strong acids, strong bases, or soluble ionic compounds. Of the options given, Lithium bromide (LiBr) is a soluble ionic compound that dissociates completely in water, making it a strong electrolyte.
Let's address the options one-by-one:
- Lithium bromide (LiBr) is a salt and dissociates fully into Li+ and Br- ions in solution, making it a strong electrolyte.
- Ethanol (CH3CH2OH) does not dissociate into ions.
- Sucrose (C12H22O11) is a nonelectrolyte and does not form ions in solution.
- Acetic acid (CH3COOH) is a weak acid and partially dissociates into ions, so it is a weak electrolyte.
- Methanol (CH3OH) does not ionize significantly and is not an electrolyte.
Therefore, the substance in the options provided that is a strong electrolyte is Lithium bromide (LiBr).