Molarity Calculator

This Molarity Calculator transforms complex solution concentration calculations into simple, accurate results. Understanding molarity is fundamental to chemistry success. Whether you’re preparing research solutions, analyzing samples, or studying for exams.

The calculator determines the molar concentration of a solution. It allows you to calculate solution concentration, solute mass, solution volume, and solute molecular weight. This versatility makes it an invaluable tool for students and professionals alike.

Molarity Calculator

Understanding the Molarity Formula

The basic molarity formula is:

Molarity (M) = Moles of Solute / Volume of Solution (L)

This can also be written as: M = n / V

Where:

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

Relationship to Mass

Since moles = mass / molar mass, we can expand the formula: Molarity = (Mass of Solute / Molar Mass) / Volume of Solution

How to Use Molarity Calculator

Our user-friendly calculator makes molarity calculations effortless:

Step 1: Enter Mass of Solute

  • Input the mass of your chemical compound
  • Use decimal values for precise calculations
  • Select appropriate units (grams, milligrams, etc.)
  • Common range: 0.1g to 1000g

Step 2: Input Molar Mass of Solute

  • Enter the molecular weight of your compound
  • Find this on periodic tables or chemical databases
  • Units are in G/Mol (grams per mole)
  • Examples: NaCl = 58.44 g/mol, H₂O = 18.02 g/mol

Step 3: Enter Volume of Solution

  • Input the total volume of your final solution
  • Select units (L, mL, etc.) from the dropdown
  • Use the final solution volume, not solvent volume
  • Ensure accuracy for precise results

Step 4: Calculate Results

The calculator automatically computes molarity and displays it in mol/L units. Results appear instantly with proper precision.

Step-by-Step Calculation Examples

Example 1: Sodium Chloride Solution

Given:

  • Mass of NaCl: 5.85 g
  • Molar mass of NaCl: 58.44 g/mol
  • Volume of solution: 500 mL = 0.5 L

Calculation:

  1. Moles of NaCl = 5.85 g ÷ 58.44 g/mol = 0.1 mol
  2. Molarity = 0.1 mol ÷ 0.5 L = 0.2 M

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