Question

Which of the following aqueous solutions contains the greatest number of ions in solution?

2.0 L of 2.00 M sodium phosphate
2.0 L of 2.00 M calcium chloride
3.0 L of 2.00 M potassium chloride
2.0 L of 2.50 M sodium chloride
1.0 L of 4.00 M potassium carbonate

Answer 1

The 2.0 L of 2.00 M sodium phosphate solution contains the greatest number of ions in solution, with a total of 16.0 moles of ions when considering its dissociation into 3 Na+ ions and 1 PO43- ion.

Step-by-step explanation:

To determine which aqueous solution contains the greatest number of ions, we need to consider the concentration of the solutions and the number of ions each compound dissociates into in water. Sodium phosphate (Na3PO4) dissociates into four ions (3 Na+ and 1 PO43-), calcium chloride (CaCl2) dissociates into three ions (1 Ca2+ and 2 Cl-), potassium chloride (KCl) dissociates into two ions (1 K+ and 1 Cl-), sodium chloride (NaCl) also dissociates into two ions (1 Na+ and 1 Cl-), and potassium carbonate (K2CO3) dissociates into three ions (2 K+ and 1 CO32-). Considering the molarity (M) and volume (L), we calculate the total number of moles of ions.

1. For 2.0 L of 2.00 M sodium phosphate, there are 2.0 L × 2.00 M × 4 ions = 16.0 moles of ions.
2. For 2.0 L of 2.00 M calcium chloride, there are 2.0 L × 2.00 M × 3 ions = 12.0 moles of ions.
3. For 3.0 L of 2.00 M potassium chloride, there are 3.0 L × 2.00 M × 2 ions = 12.0 moles of ions.
4. For 2.0 L of 2.50 M sodium chloride, there are 2.0 L × 2.50 M × 2 ions = 10.0 moles of ions.
5. For 1.0 L of 4.00 M potassium carbonate, there are 1.0 L × 4.00 M × 3 ions = 12.0 moles of ions.

Therefore, the aqueous solution that contains the greatest number of ions is the 2.0 L of 2.00 M sodium phosphate.