1. What is Molecular Weight?

Molecular weight (MW) is the sum of the atomic weights of all atoms in a molecule. It's expressed in atomic mass units (amu) or grams per mole (g/mol) and is crucial for stoichiometric calculations in chemistry.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( MW \) — Molecular weight (g/mol)
• Each element's atomic mass is multiplied by its count in the molecule
• The sum of all atomic masses gives the molecular weight

Explanation: The calculator parses the chemical formula, identifies each element and its count, then sums their atomic masses.

3. Importance of Molecular Weight

Details: Molecular weight is essential for preparing solutions, calculating molarity, determining reaction yields, and in analytical techniques like mass spectrometry.

4. Using the Calculator

Tips: Enter the chemical formula using standard notation (e.g., H2O, C6H12O6). Element symbols are case-sensitive (Na for sodium, not NA).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular weight and molar mass?
A: They are numerically identical but molecular weight is dimensionless while molar mass has units of g/mol.

Q2: How are atomic masses determined?
A: Atomic masses are weighted averages of isotopic masses based on their natural abundance.

Q3: Does the calculator work for complex formulas?
A: Yes, but it doesn't handle parentheses or hydrates (like CuSO4·5H2O). For these, calculate each part separately.

Q4: Why are atomic masses not whole numbers?
A: Most elements have multiple isotopes with different masses, so the atomic mass is an average weighted by isotopic abundance.

Q5: How accurate are these calculations?
A: The calculator uses standard atomic weights. For precise work, use exact isotopic masses if needed.