ou dissolve 4.4 g of sodium chloride in 500 mL of water, what is the molarity of sodium cations in the solution as moles per litre?

Sure, here are the steps to calculate the molarity of sodium cations in the solution:

1. First, we need to convert the mass of sodium chloride (NaCl) to moles. The molar mass of NaCl is approximately 58.44 g/mol. So, 4.4 g of NaCl is 4.4 g / 58.44 g/mol = 0.0753 mol.

2. Next, we need to convert the volume of the solution from milliliters to liters. 500 mL is equal to 0.5 L.

3. Molarity is defined as the number of moles of solute per liter of solution. So, the molarity of the NaCl solution is 0.0753 mol / 0.5 L = 0.1506 M.

4. However, each unit of NaCl dissociates into one sodium cation (Na+) and one chloride anion (Cl-) in solution. Therefore, the molarity of sodium cations in the solution is also 0.1506 M.