Molarity Calculator

How it works

Calculate the molar concentration of a solute in a solution by mass, volume, and molar mass.

Calculate the molar concentration (M) of a chemical solution

Description

The Molarity Calculator is an essential tool for chemistry students, researchers, and lab technicians. Molarity ($M$) is a measure of the concentration of a solute in a solution, expressed as the number of moles per liter. This tool automates the two-step process of converting mass to moles and then calculating the concentration based on the final volume of the solution.

Inputs

• Mass of Solute (g): The weight of the chemical powder or substance you are dissolving.
• Volume of Solution (L): The final total volume of the liquid after mixing.
• Molecular Weight (g/mol): The molar mass of the substance (found on the periodic table or the product bottle).

Outputs

• Molarity: The concentration expressed in M (mol/L).

Chart

• N/A: This tool provides precision numeric chemistry results.

“Good to Know”

• The Formula: $\text{Molarity} = \frac{(\text{Mass} / \text{Molecular Weight})}{\text{Volume}}$.
• Solution vs. Solvent: Always measure the final volume of the mixed solution. Adding a solid to a liquid can change the total volume slightly!
• Standard Reference: A common saline solution (NaCl) has a molecular weight of approximately 58.44 g/mol.
• Significant Figures: Lab results often require specific precision. This tool provides 4 decimal places for accuracy.

Examples

Example 1: Saline Solution

• Input: Mass: 5.8g, Volume: 1L, Mol Weight: 58.44
• Output: 0.0992 M

Example 2: Concentrated Sugar Water

• Input: Mass: 100g, Volume: 0.5L, Mol Weight: 342.3 (Sucrose)
• Output: 0.5843 M

Example 3: Small Sample

• Input: Mass: 1g, Volume: 0.1L (100ml), Mol Weight: 40.0 (NaOH)
• Output: 0.2500 M