1. What is Molecular Weight?

Molecular weight (MW) is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It's calculated by dividing the mass of a sample by the number of moles in that sample.

2. How Does the Calculator Work?

The calculator uses the molecular weight formula:

Where:

• \( MW \) — Molecular weight (g/mol)
• \( m \) — Mass of the substance (g)
• \( n \) — Number of moles (mol)

Explanation: This simple formula relates the mass of a substance to its molar quantity, allowing calculation of its molecular weight.

3. Importance of Molecular Weight

Details: Molecular weight is fundamental in chemistry for stoichiometric calculations, preparing solutions, and determining reaction yields. It's essential for converting between mass and moles of a substance.

4. Using the Calculator

Tips: Enter the mass in grams and the number of 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?
A: Moles can be determined by measuring mass and dividing by the known molecular weight, or from the number of particles using Avogadro's number.

Q3: Why is molecular weight important in chemistry?
A: It allows conversion between mass and number of particles, essential for reaction stoichiometry and solution preparation.

Q4: Can this calculator be used for compounds and elements?
A: Yes, the formula works for any chemical substance where you know both the mass and number of moles.

Q5: What are typical molecular weight ranges?
A: Simple molecules range from ~2 g/mol (H₂) to several hundred, while polymers can have molecular weights in the millions.