If you dissolve 5.0g of NaCl in 3.0 liters of water, what is the concentration of the solution?
To find the concentration of a solution, you need to determine the amount of solute (in this case, NaCl) dissolved in a given volume of solvent (in this case, water). The concentration is typically expressed in units of molarity (mol/L).
To calculate the concentration, you can follow these steps:
1. Convert the mass of NaCl to moles:
- Find the molar mass of NaCl. Sodium (Na) has a molar mass of 22.99 g/mol, and chlorine (Cl) has a molar mass of 35.45 g/mol. Therefore, the molar mass of NaCl is 22.99 + 35.45 = 58.44 g/mol.
- Divide the mass of NaCl (5.0g) by its molar mass (58.44 g/mol) to get the number of moles:
5.0g NaCl ÷ 58.44 g/mol = 0.086 mol NaCl.
2. Calculate the concentration:
- Divide the number of moles of NaCl (0.086 mol) by the volume of the solution (3.0 L) to find the concentration:
0.086 mol ÷ 3.0 L = 0.029 M.
Therefore, the concentration of the NaCl solution is 0.029 M (moles per liter).