Molarity Calculator (Volume, Moles, Concentration)

Calculate Molarity (M), Volume (L/mL), or Moles (mol/mmol) of a chemical solution given the other two values. Performs "mL to moles" conversion via concentration.

Molarity Calculator (Concentration Tool)

Calculate the Molarity (M), Volume (V), or Moles (n) for a chemical solution. This tool uses the relationship M = n / V. Enter any two values to compute the third.

Note: This calculator works for **solutions** with a known concentration (Molarity). It cannot directly convert mL to moles for pure substances without density and molar mass data.

Solution Parameters

Enter values in exactly two fields:

mol/L
Concentration in moles per liter.
Amount of solute.

Understanding Molarity, Volume, and Moles

In chemistry, understanding the relationship between the amount of a substance (solute) dissolved in a certain amount of solution is crucial. This relationship is defined by concentration, most commonly **Molarity**.

  • Moles (n): Represents the amount of a chemical substance. One mole contains Avogadro's number ($6.022 \times 10^{23}$) of particles (atoms, molecules, ions). Unit: mol or mmol (millimole = 0.001 mol).
  • Volume (V): The amount of space the solution occupies. Unit: L (liter) or mL (milliliter = 0.001 L).
  • Molarity (M): The concentration of a solution expressed as the number of moles of solute per liter of solution. Unit: mol/L (often abbreviated as M).

The Core Formula:

These three quantities are linked by the definition of molarity:

Molarity (M) = $\frac{\text{Moles of Solute (n)}}{\text{Volume of Solution (V in Liters)}}$

This calculator uses rearrangements of this formula to find any one value if the other two are known:

  • Moles (n) = Molarity (M) × Volume (V in Liters)    *(This performs the "mL to moles" conversion)*
  • Volume (V in Liters) = Moles (n) / Molarity (M)

Use Cases:

  • Solution Preparation: Calculating the amount of solute (in moles, which can be converted to grams using molar mass) needed to achieve a desired molarity in a specific volume.
  • Dilution Calculations: (Requires M1V1=M2V2, often used alongside this calculator).
  • Stoichiometry: Determining reacting amounts in chemical reactions involving solutions of known molarity.
  • Lab Analysis: Calculating concentrations from titration data (volume and moles reacted).

Frequently Asked Questions (FAQs)

How does this convert mL to Moles?

It uses the formula: Moles = Molarity × Volume (in Liters). You must provide the Volume (you can enter it in mL, the calculator converts it to L) AND the Molarity (concentration in mol/L) of the solution. The calculator then computes the moles of solute present in that volume.

Can I use this for pure liquids or solids?

No. This calculator is specifically for **solutions** where concentration (Molarity) is relevant. To convert volume (mL) of a pure substance to moles, you would need its **density** (to find mass) and its **molar mass** (to find moles from mass).

What is the difference between mol and mmol?

A millimole (mmol) is one-thousandth of a mole. 1 mol = 1000 mmol. Using mmol is often convenient when working with small volumes (mL).

What if I only know the mass (grams) of the solute?

You need the substance's **Molar Mass** (g/mol, often found on the periodic table or chemical container) to convert grams to moles: Moles = Mass (g) / Molar Mass (g/mol). Once you have moles, you can use this calculator with the volume to find molarity, or with molarity to find volume.

How accurate are the results?

The calculations are based on the exact mathematical formulas. The accuracy of the result depends entirely on the accuracy of the values you input for volume, molarity, or moles.

Magdy Hassan
Magdy Hassan

Father, Engineer & Calculator Enthusiast I am a proud father and a passionate engineer with a strong background in web development and a keen interest in creating useful tools and applications. My journey in programming started with a simple calculator project, which eventually led me to create this comprehensive unit conversion platform. This calculator website is my way of giving back to the community by providing free, easy-to-use tools that help people in their daily lives. I'm constantly working on adding new features and improving the existing ones to make the platform even more useful.

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