Parentheses
A subscript outside parentheses multiplies every element inside the group. Ca(NO3)2 has one calcium, two nitrogens, and six oxygens.
Formula tool
Chemical Formula Calculator
Break a formula into element counts, expand parentheses, and estimate molar mass for common chemistry homework formulas.
Try H2O, Ca(NO3)2, Al2(SO4)3, or CuSO4.5H2O. Capitalization matters because Co and CO mean different things.
Formula breakdown
Ca(NO3)2
- Total atoms
- 9
- Elements
- 3
- Molar mass
- 164.086 g/mol
| Element | Atoms | Atomic mass | Mass contribution |
|---|---|---|---|
| Calcium (Ca) | 1 | 40.078 | 40.078 |
| Nitrogen (N) | 2 | 14.007 | 28.014 |
| Oxygen (O) | 6 | 15.999 | 95.994 |
Atomic masses are classroom approximations; use a primary reference for precision analytical work.
Hydrates
A dot separates waters of hydration. CuSO4.5H2O counts the atoms in copper sulfate and five water molecules.
Molar mass
The molar mass is calculated from classroom atomic mass values, so use a lab reference when precision matters.