How to Calculate the Concentration of Solution

Solution Concentration Calculator

Use this calculator to determine the concentration of a solution based on the mass of the solute and the total volume of the solution.

Mass of Solute: grams (g) milligrams (mg) kilograms (kg)

Volume of Solution: liters (L) milliliters (mL)

Understanding Solution Concentration

Solution concentration is a fundamental concept in chemistry, indicating the amount of solute dissolved in a given amount of solvent or solution. It's a crucial metric in various scientific fields, including chemistry, biology, pharmacology, and environmental science, as it directly impacts the properties and reactivity of a solution.

What is Solute and Solvent?

Solute: The substance that is dissolved in a solvent to form a solution. For example, salt in saltwater.
Solvent: The substance that dissolves the solute. Water is a common solvent, often called the "universal solvent."

Common Units of Concentration

While there are many ways to express concentration, this calculator focuses on two common methods:

Mass/Volume Concentration (e.g., g/L, mg/mL): This expresses the mass of the solute per unit volume of the solution. It's widely used in many practical applications.
Percent Weight/Volume (% w/v): This represents the number of grams of solute in 100 milliliters of solution. It's frequently used in pharmaceutical and clinical settings.

How to Use the Calculator

Enter Mass of Solute: Input the amount of the substance you are dissolving. Select the appropriate unit (grams, milligrams, or kilograms).
Enter Volume of Solution: Input the total volume of the final solution. Select the appropriate unit (liters or milliliters).
Click "Calculate Concentration": The calculator will then display the concentration in grams per liter (g/L) and as a percentage weight/volume (% w/v).

Example Calculation

Let's say you dissolve 15 grams of sodium chloride (NaCl) in enough water to make a total solution volume of 750 milliliters.

Mass of Solute: 15 g
Volume of Solution: 750 mL

Using the calculator:

Input 15 for Mass of Solute, select grams (g).
Input 750 for Volume of Solution, select milliliters (mL).
The calculator would output:
- Concentration: 20.0000 g/L
- Concentration: 2.0000 % (w/v)

This means there are 20 grams of NaCl in every liter of solution, or 2 grams of NaCl in every 100 mL of solution.

/* Basic styling for the calculator – can be customized */ .concentration-calculator { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f9f9f9; border: 1px solid #ddd; padding: 20px; border-radius: 8px; max-width: 600px; margin: 20px auto; box-shadow: 0 2px 4px rgba(0,0,0,0.1); } .concentration-calculator h2 { color: #333; text-align: center; margin-bottom: 20px; } .concentration-calculator .calculator-input-group { margin-bottom: 15px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; } .concentration-calculator label { flex: 1 1 150px; font-weight: bold; color: #555; } .concentration-calculator input[type="number"], .concentration-calculator select { flex: 2 1 180px; padding: 10px; border: 1px solid #ccc; border-radius: 4px; font-size: 16px; } .concentration-calculator button { display: block; width: 100%; padding: 12px 20px; background-color: #007bff; color: white; border: none; border-radius: 4px; font-size: 18px; cursor: pointer; transition: background-color 0.3s ease; margin-top: 20px; } .concentration-calculator button:hover { background-color: #0056b3; } .concentration-calculator .calculator-result { margin-top: 25px; padding: 15px; background-color: #e9f7ef; border: 1px solid #d4edda; border-radius: 4px; font-size: 1.1em; color: #155724; text-align: center; font-weight: bold; } .concentration-calculator .calculator-result p { margin: 5px 0; } .calculator-article { margin-top: 30px; border-top: 1px solid #eee; padding-top: 20px; } .calculator-article h3, .calculator-article h4 { color: #333; margin-top: 20px; margin-bottom: 10px; } .calculator-article p, .calculator-article ul { color: #666; line-height: 1.6; margin-bottom: 10px; } .calculator-article ul { list-style-type: disc; margin-left: 20px; } .calculator-article ol { list-style-type: decimal; margin-left: 20px; } function calculateConcentration() { // Get input values var soluteMassInput = document.getElementById("soluteMass").value; var soluteMassUnit = document.getElementById("soluteMassUnit").value; var solutionVolumeInput = document.getElementById("solutionVolume").value; var solutionVolumeUnit = document.getElementById("solutionVolumeUnit").value; var resultDiv = document.getElementById("concentrationResult"); // Validate inputs var soluteMass = parseFloat(soluteMassInput); var solutionVolume = parseFloat(solutionVolumeInput); if (isNaN(soluteMass) || soluteMass < 0) { resultDiv.innerHTML = "Please enter a valid non-negative number for Mass of Solute."; return; } if (isNaN(solutionVolume) || solutionVolume <= 0) { // Volume cannot be zero or negative resultDiv.innerHTML = "Please enter a valid positive number for Volume of Solution."; return; } // Convert solute mass to grams var soluteMass_g; if (soluteMassUnit === "mg") { soluteMass_g = soluteMass / 1000; } else if (soluteMassUnit === "kg") { soluteMass_g = soluteMass * 1000; } else { // default to grams soluteMass_g = soluteMass; } // Convert solution volume to liters for g/L calculation var solutionVolume_L; if (solutionVolumeUnit === "mL") { solutionVolume_L = solutionVolume / 1000; } else { // default to liters solutionVolume_L = solutionVolume; } // Calculate Concentration (g/L) var concentration_g_L = soluteMass_g / solutionVolume_L; // Convert solution volume to mL for % (w/v) calculation var solutionVolume_mL; if (solutionVolumeUnit === "L") { solutionVolume_mL = solutionVolume * 1000; } else { // default to mL solutionVolume_mL = solutionVolume; } // Calculate Concentration (% w/v) – grams per 100 mL var concentration_percent_w_v = (soluteMass_g / solutionVolume_mL) * 100; // Display results resultDiv.innerHTML = "Calculated Concentration:" + "" + concentration_g_L.toFixed(4) + " g/L" + "" + concentration_percent_w_v.toFixed(4) + " % (w/v)"; }