1. What is Molecular Mass?

Molecular mass (or molecular weight) is the sum of the atomic masses of all the atoms in a molecule. It's expressed in atomic mass units (u) or grams per mole (g/mol) and is crucial for various chemical calculations.

2. How the Calculator Works

The calculator uses the formula:

Example: For water (H₂O):

• 2 Hydrogen atoms: 2 × 1.008 g/mol = 2.016 g/mol
• 1 Oxygen atom: 1 × 15.999 g/mol = 15.999 g/mol
• Total molecular mass = 2.016 + 15.999 = 18.015 g/mol

3. Importance of Molecular Mass

Applications: Molecular mass is essential for:

• Calculating molar concentrations
• Determining reaction stoichiometry
• Preparing solutions with specific molarity
• Converting between mass and moles of a substance

4. How to Use the Calculator

Instructions:

1. Enter elements and their counts in the format: ElementSymbolCount (e.g., H2 O1 for water)
2. Element symbols are case-sensitive (first letter uppercase, following letters lowercase)
3. If count is omitted, it's assumed to be 1
4. Separate different elements with spaces

Examples:

• Water: H2 O1 (or simply H2 O)
• Glucose: C6 H12 O6
• Sulfuric acid: H2 S1 O4

5. Frequently Asked Questions

Q1: What's the difference between molecular mass and molar mass?
A: They're numerically identical but molar mass refers to one mole of substance (6.022×10²³ molecules).

Q2: How accurate are the atomic masses used?
A: We use standard atomic weights based on IUPAC recommendations, accounting for natural isotope distributions.

Q3: Can I calculate formula mass for ionic compounds?
A: Yes, the same principle applies to ionic compounds (called formula mass rather than molecular mass).

Q4: Why are some atomic masses not whole numbers?
A: Atomic masses account for different isotopes and their natural abundances.

Q5: What if my compound contains an element not listed?
A: The calculator currently supports common elements. More elements can be added upon request.

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