Solution Concentration Calculator

What is Solution Concentration?

Solution concentration describes how much solute is present in a given amount of solution. Common units include molarity (M, moles per liter), mass concentration (g/L), percent weight/volume (% w/v), and parts per million (ppm). This calculator helps you compute these values from the solute mass, solution volume, and molar mass.

Key Concepts & Formulas

The main formulas used by this calculator are:

Example

Suppose you dissolve 10 g of sodium chloride (NaCl, molar mass ≈ 58.5 g·mol⁻¹) in 1.00 L of water. Using the calculator defaults you will get:

• Moles = 10 / 58.5 ≈ 0.17094 mol
• Molarity = 0.17094 mol / 1.00 L ≈ 0.17094 M
• Mass concentration = 10 g / 1.00 L = 10 g·L⁻¹
• % (w/v) = 10 g·L⁻¹ × 0.1 = 1.0% (w/v)
• ppm ≈ 10 g·L⁻¹ × 1000 = 10000 ppm (approx)

Practical Notes

- This calculator assumes solution volume is provided in liters. For volumes in mL, convert to liters by dividing by 1000.

- ppm is given as an approximation (mg·L⁻¹) and is valid for dilute aqueous solutions where the density is close to 1. For more precise work, use mass of solution rather than volume-based approximations.

- The calculator updates automatically as you change inputs — no calculate button is required.

Frequently Asked Questions (FAQ)

Can I calculate molality with this tool?

Molality (mol·kg⁻¹) requires the mass of the solvent (in kilograms). This calculator uses solution volume, so it cannot compute molality accurately without additional information about solution mass or density.

Why is ppm approximated from g/L?

For dilute aqueous solutions, 1 mg·L⁻¹ is approximately 1 ppm because water density is ~1 kg·L⁻¹. For concentrated solutions or non-aqueous solvents, ppm should be evaluated from mass ratios.

How do I convert mL to L?

Divide the volume in milliliters by 1000. For example, 250 mL = 0.250 L.