1. What is Molecular Weight?

Molecular weight (or molecular mass) is the sum of the atomic weights of all atoms in a molecule. It's expressed in atomic mass units (u) or grams per mole (g/mol).

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( atomic\_mw \) — Atomic weight of each element (g/mol)
• \( num\_atoms \) — Number of atoms of each element in the molecule

Explanation: The calculator parses the chemical formula, identifies each element and its count, then sums the products of atomic weights and atom counts.

3. Importance of Molecular Weight

Details: Molecular weight is crucial for stoichiometric calculations, preparing molar solutions, determining empirical formulas, and many chemical analyses.

4. Using the Calculator

Tips: Enter the chemical formula using standard notation (e.g., H2O, C6H12O6). Element symbols must start with uppercase letters followed by lowercase if needed. Numbers indicate atom counts (1 is omitted).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular weight and molar mass?
A: They are numerically identical but molar mass is expressed in grams per mole (g/mol) while molecular weight is dimensionless.

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

Q3: Does the calculator work for ionic compounds?
A: Yes, it works for any chemical formula, though technically ionic compounds have formula weights rather than molecular weights.

Q4: What if my element isn't recognized?
A: The calculator currently supports common elements. More can be added to the atomic weights array in the code.

Q5: How accurate are the calculations?
A: Accuracy depends on the precision of the atomic weights used. The calculator uses standard atomic weights from IUPAC.