Molarity Calculator

How to Calculate Molarity

Molarity is a fundamental concept in chemistry that expresses the concentration of a solute in a solution. It is defined as the number of moles of solute per liter of solution. Understanding how to calculate molarity is crucial for various chemical calculations and laboratory work.

What is the Molarity Formula?

The molarity formula is:

\[ M = \frac{n}{V} \]

Where:

• M = Molarity (mol/L or M)
• n = Number of moles of solute (mol)
• V = Volume of solution (L)

What are the calculation steps?

1. Determine the number of moles of solute
2. Measure the volume of the solution in liters
3. Divide the number of moles by the volume in liters

Example Calculation

Let's calculate the molarity of a solution containing 2.5 moles of NaCl dissolved in 500 mL of water:

Given:

• n = 2.5 mol NaCl
• V = 500 mL = 0.5 L

Step 1: Identify the formula

We'll use: M = n / V

Step 2: Substitute the values

M = 2.5 mol / 0.5 L

Step 3: Solve the equation

M = 5 mol/L

Therefore, the molarity of the NaCl solution is 5 M (5 molar).

Diagram of Molarity

The following diagram illustrates the concept of molarity:

This diagram shows a solution with a volume of 1 liter containing n moles of solute. The molarity of the solution is the number of moles of solute (n) divided by the volume of the solution in liters (1 L in this case).