1. What is Relative Molecular Mass?

Relative Molecular Mass (RMM), also known as molecular weight, is the sum of the atomic masses of all the atoms in a molecule. It's a dimensionless quantity that helps in stoichiometric calculations in chemistry.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( atomic\_masses \) — Standard atomic weights of elements
• \( counts \) — Number of atoms of each element in the molecule

Explanation: The calculator parses the chemical formula, looks up each element's atomic mass, multiplies by the atom count, and sums all values.

3. Importance of RMM Calculation

Details: RMM is essential for preparing solutions with specific molar concentrations, determining empirical formulas, and balancing chemical equations.

4. Using the Calculator

Tips: Enter the chemical formula using standard notation (e.g., H2O for water, C6H12O6 for glucose). Element symbols are case-sensitive (first letter uppercase, second lowercase if present).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between RMM and molar mass?
A: RMM is dimensionless, while molar mass has units of g/mol. Numerically they're equal when molar mass is expressed in g/mol.

Q2: How accurate are the atomic masses used?
A: The calculator uses standard atomic weights (IUPAC values) with 4 decimal places for common elements.

Q3: Can I use this for ionic compounds?
A: Yes, the same calculation applies to formula units of ionic compounds (e.g., NaCl).

Q4: What about hydrates or other complex formulas?
A: Enter the full formula including water molecules (e.g., CuSO4·5H2O for copper(II) sulfate pentahydrate).

Q5: Why doesn't my complex formula work?
A: The calculator currently supports basic formulas with elements followed by optional counts. Complex notation may require preprocessing.