1. What is Molecular Weight?

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

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( MW \) — Molecular weight in g/mol
• \( \sum \) — Sum of all atomic masses in the molecule
• Atomic masses are based on standard atomic weights

Explanation: The calculator parses the chemical structure and sums the atomic weights of all constituent atoms.

3. Importance of Molecular Weight

Details: Molecular weight is crucial for stoichiometric calculations, preparing solutions, determining reaction yields, and in drug development (pharmacokinetics).

4. Using the Calculator

Tips: Enter the chemical structure using SMILES notation or draw the molecule in the provided interface. The calculator will parse the structure and calculate the molecular weight.

5. Frequently Asked Questions (FAQ)

Q1: What is SMILES notation?
A: SMILES (Simplified Molecular Input Line Entry System) is a string notation for describing molecular structures.

Q2: How accurate is this calculator?
A: The calculator uses standard atomic weights. For precise work, use isotopic masses and consider isotopic distribution.

Q3: Can it handle complex molecules?
A: Yes, the calculator can handle complex organic molecules, polymers, and inorganic compounds.

Q4: What about hydrates or salts?
A: Include water molecules or counterions in your structure input to account for their mass.

Q5: How is molecular weight different from formula weight?
A: For ionic compounds, the term formula weight is often used, but the calculation is essentially the same.