Which of the following 1.0 molar (1.0 M) solutions contains the greatest total number of dissolved particles?

• A. 1.0 M CaCl_2
• B. 1.0 M C_6H_{12}O_6 (glucose)
• C. 1.0 M KNO_3
• D. 1.0 M NaCl

Answer: (A)

Verified step by step guidance

1. Identify that the total number of dissolved particles in solution depends on the solute's dissociation into ions. Non-electrolytes like glucose do not dissociate, while ionic compounds dissociate into their constituent ions.
2. Write the dissociation equations for each ionic compound: - For CaCl_2: \(\mathrm{CaCl_2 \rightarrow Ca^{2+} + 2Cl^-}\) - For KNO_3: \(\mathrm{KNO_3 \rightarrow K^+ + NO_3^-}\) - For NaCl: \(\mathrm{NaCl \rightarrow Na^+ + Cl^-}\)
3. Determine the number of particles each formula unit produces upon dissociation: - CaCl_2 produces 3 particles (1 Ca^{2+} + 2 Cl^-) - KNO_3 produces 2 particles (1 K^+ + 1 NO_3^-) - NaCl produces 2 particles (1 Na^+ + 1 Cl^-) - Glucose (C_6H_{12}O_6) produces 1 particle (no dissociation)
4. Since all solutions are 1.0 M, multiply the molarity by the number of particles produced per formula unit to find the total particle concentration: - Total particles = Molarity × number of particles per formula unit
5. Compare the total particle concentrations for each solution. The solution with the greatest total number of dissolved particles is the one with the highest product from step 4.