1. What is Molecular Weight?

Molecular weight (MW) is the mass of one mole of a substance, expressed in grams per mole (g/mol). It's calculated by summing the atomic weights of all atoms in a molecule.

2. How Does the Calculator Work?

The calculator uses the molecular weight formula:

Where:

• \( MW \) — Molecular weight (g/mol)
• \( g \) — Mass of substance (grams)
• \( n \) — Amount of substance (moles)

Explanation: The formula relates the mass of a substance to the number of moles present, allowing calculation of the weight per mole.

3. Importance of Molecular Weight Calculation

Details: Molecular weight is essential for preparing solutions, stoichiometric calculations, and determining reaction yields in chemistry.

4. Using the Calculator

Tips: Enter the mass in grams and amount in moles. Both values must be positive numbers. The calculator will compute the molecular weight in g/mol.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular weight and molar mass?
A: They are numerically identical but molecular weight refers to molecules while molar mass can refer to any chemical entity (atoms, ions, etc.).

Q2: How do I find the number of moles if I know the molecular weight?
A: Rearrange the formula: \( n = \frac{g}{MW} \). Divide mass by molecular weight to get moles.

Q3: Why is molecular weight important in solution preparation?
A: It allows calculation of how much solute to add to achieve a desired molar concentration (e.g., 1M solution).

Q4: Does molecular weight change with temperature or pressure?
A: No, molecular weight is an intrinsic property of a substance and doesn't vary with physical conditions.

Q5: How accurate is this calculator?
A: The calculation is mathematically exact, but accuracy depends on the precision of your input measurements.