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 (u) 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 (g/mol)
• \( atomic\_masses \) — Array of atomic masses for each element in the molecule

Explanation: The calculator sums the atomic weights of all atoms in the molecule, accounting for the quantity of each element.

3. Importance of Molecular Weight

Details: Molecular weight is essential for preparing solutions, calculating molarity, determining reaction yields, and understanding physical properties of substances.

4. Using the Calculator

Tips:

• Enter element symbols (e.g., C, H, O) separated by commas
• Enter corresponding quantities separated by commas
• Example: For H2O, enter "H, O" in elements and "2, 1" in quantities
• Element symbols are case-sensitive (first letter capitalized)

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between molecular weight and formula weight?
A: Molecular weight refers to molecules, while formula weight is used for ionic compounds. The calculation method is essentially the same.

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

Q3: Can I calculate MW for complex formulas?
A: Yes, just include all elements and their counts. For example, for C6H12O6 (glucose), enter "C,H,O" and "6,12,6".

Q4: What if my element isn't in the database?
A: The calculator includes common elements. For others, please use a more comprehensive periodic table.

Q5: Why is molecular weight important in solutions?
A: It's needed to convert between mass and moles (using n = m/MW), which is fundamental for preparing solutions of specific molarity.

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