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 molecular weight formula:

Where:

• \( MW \) — Molecular weight in g/mol
• \( \text{atomic masses} \) — Standard atomic weights of elements
• \( \text{counts} \) — Number of each atom in the molecule

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

3. Importance of Molecular Weight

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

4. Using the Calculator

Tips: Enter the chemical formula using standard notation (e.g., H2O for water, C6H12O6 for glucose). Case matters - element symbols start with uppercase letters.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular weight and molar mass?
A: They are numerically equivalent but molecular weight refers to single molecules while molar mass refers to one mole of substance.

Q2: How accurate is this calculator?
A: It uses standard atomic weights. For precise work, use isotopic-specific weights if needed.

Q3: What about hydrates or salts?
A: Include water molecules or counterions in the formula (e.g., CuSO4·5H2O for copper sulfate pentahydrate).

Q4: Can it handle complex formulas?
A: It handles most standard chemical formulas but may not parse very complex notations or polymers.

Q5: Where do the atomic weights come from?
A: Standard atomic weights are from IUPAC recommendations based on natural isotopic abundances.