1. What is Molecular Weight?

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

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( MW \) — Molecular weight (g/mol)
• \( atomic\_masses \) — Atomic weights of elements (g/mol)
• \( counts \) — Number of each atom in the molecule

Explanation: The calculator parses the chemical formula, looks up atomic weights, and sums the products of atomic weights and their counts in the molecule.

3. Importance of Molecular Weight

Details: Molecular weight is crucial for preparing solutions, stoichiometric calculations, determining reaction yields, and converting between mass and moles in chemical equations.

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 followed by lowercase letters.

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 the preferred term in modern chemistry. Molecular weight is a somewhat older term.

Q2: How accurate are these calculations?
A: They use standard atomic weights. For precise work, use isotope-specific masses if needed.

Q3: Can this calculator handle complex formulas?
A: It handles most standard chemical formulas but may not parse very complex notations or parentheses.

Q4: What about hydrates or salts?
A: Enter them with dots (e.g., CuSO4.5H2O for copper sulfate pentahydrate).

Q5: Why is molecular weight important in solutions?
A: It's used to calculate molarity (mol/L) from mass concentration (g/L) and vice versa.