A solution is a mixture of two or more substances, where one substance is dissolved in another.

The concentration of a solution is a measure of how much of the solute (the dissolved substance) is present in a given amount of the solvent (the substance in which the solute is dissolved).

Molarity (M):

1. This is the most common way of expressing the concentration of a solution, and it is defined as the number of moles of solute per liter of solution.

2. For example, a solution with a concentration of 0.1 M NaCl contains 0.1 moles of NaCl in 1 liter of solution.

Molality

1. Molality (m): Molality is similar to molarity, but it is defined as the number of moles of solute per kilogram of solvent.

2. Molality is often used when working with solutions at high temperatures or pressures, where the volume of the solution may change significantly.

Mass Percent

1. Mass percent (% m/m): Mass percent is a way of expressing the concentration of a solution as the percentage of the mass of the solute in the total mass of the solution.

2. For example, a 10% m/m solution of glucose contains 10 grams of glucose per 100 grams of solution.

Volume Percent

1. Volume percent (% v/v): Volume percent is similar to mass percent, but it expresses the concentration of a solution as the percentage of the volume of the solute in the total volume of the solution. For example, a 20% v/v solution of ethanol contains 20 mL of ethanol per 100 mL of solution.

Mole Fraction

1. Mole fraction (X): Mole fraction is a way of expressing the concentration of a solution as the number of moles of solute divided by the total number of moles in the solution.

2. It is often used in thermodynamics and other physical chemistry calculations.

Part per million

1. Parts per million (ppm): Parts per million is a way of expressing very dilute concentrations of a solute in a solution.

2. It is defined as the number of parts of solute per million parts of solution. For example, a solution with a concentration of 10 ppm of lead contains 10 parts of lead per million parts of solution.

Explanation Slide...

20g / (180g+ 20g) x 100 = 10 %