Periodic table

Choose an element to see its atomic number and CIAAW standard atomic weight, then calculate the mass of an entered amount.

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Element symbol, name or atomic number

Amount (mol)

Answer

…

Choose an element to see its atomic number and CIAAW standard atomic weight, then calculate the mass of an entered amount.

More results

Precision and calculation record

Decimal places in numeric results and text downloads

Rounding changes displayed numbers, not the calculation. Text, fractions, matrices and CSV schedules keep their own formatting. Automatic keeps up to 12 significant digits, with money shown to cents where applicable.

Saved scenario

Save the current answer, then change an input to compare. This clears when you leave.

Formula and assumptions

The 2024 CIAAW abridged table contains 118 elements. A dash means no standard atomic weight is assigned; it is not zero or a selected isotope mass. Natural isotopic variation and modified materials can differ from the reference. This table does not predict isotope composition or chemical behavior.

Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.

Choose an element

Tap a symbol to use it in the calculation. On a narrow screen, scroll the table sideways or enter a name above.

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Updated 2026-09-29

Using Periodic table

Choose an element to see its atomic number and CIAAW standard atomic weight, then calculate the mass of an entered amount.

Next: Molar mass calculator

Next: Molarity calculator

A worked example

For element symbol, name or atomic number = C, amount (mol) = 2, mass of entered amount (g) = 24.022.

Before you use the result

Example results for amount (mol)

These examples use Element symbol, name or atomic number: C. They are reference calculations, not recommended settings.

Amount (mol)	Mass of entered amount (g)
1	12.011
2	24.022
4	48.044

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