Which of the following compounds should not break up into ions when dissolved in water?

• A. NaCl (sodium chloride)
• B. C_6H_{12}O_6 (glucose)
• C. KNO_3 (potassium nitrate)
• D. HCl (hydrochloric acid)

Answer: (B)

Verified step by step guidance

1. Understand that compounds that break up into ions in water are called electrolytes, and they typically include ionic compounds and strong acids or bases.
2. Identify that NaCl (sodium chloride) is an ionic compound that dissociates into Na\^{+} and Cl\^{-} ions in water.
3. Recognize that KNO_3 (potassium nitrate) is also an ionic compound that dissociates into K\^{+} and NO_3\^{-} ions in water.
4. Know that HCl (hydrochloric acid) is a strong acid that ionizes completely in water to form H\^{+} and Cl\^{-} ions.
5. Realize that C_6H_{12}O_6 (glucose) is a molecular compound (a covalent compound) that dissolves in water but does not break up into ions; it remains as intact molecules.