Which of the following pairs of compounds is most likely to form a solution when mixed?

• A. NaCl and H2O
• B. CH4 and H2O
• C. AgCl and C6H6
• D. C6H12O6 and C6H14

Answer: (A)

Verified step by step guidance

1. Understand the principle of 'like dissolves like,' which means polar solvents tend to dissolve polar solutes, and nonpolar solvents tend to dissolve nonpolar solutes.
2. Identify the polarity of each compound in the pairs: NaCl is an ionic compound (highly polar), H2O is a polar solvent; CH4 is nonpolar, H2O is polar; AgCl is ionic but poorly soluble, C6H6 (benzene) is nonpolar; C6H12O6 (a sugar) is polar, C6H14 (hexane) is nonpolar.
3. Evaluate the interactions: NaCl dissociates into ions in water due to strong ion-dipole interactions, making it highly soluble; CH4 does not dissolve well in water because it is nonpolar; AgCl is sparingly soluble in water and does not dissolve well in benzene; C6H12O6 is polar and soluble in water but not in nonpolar hexane.
4. Conclude that the pair with the strongest favorable interactions and highest likelihood of forming a solution is NaCl and H2O due to their polar and ionic nature respectively.
5. Remember that solubility depends on the ability of the solvent to stabilize the solute particles through intermolecular forces such as ion-dipole or hydrogen bonding.