Calculating the relative molecular mass (or molar mass) of a chemical compound is a fundamental skill in chemistry. To do this, you need to know the correct chemical formula of the compound and the atomic masses of its individual elements. Let's calculate it for Ammonium Dichromate.
The relative molecular mass of Ammonium Dichromate is 252 u (or 252 g/mol).
Ammonium dichromate is an orange crystalline solid.
It is famously used in chemistry labs for the 'chemical volcano' demonstration because it decomposes violently upon heating, producing green chromium(III) oxide ash.
The chemical formula for Ammonium dichromate is $(NH_4)_2Cr_2O_7$.
Before we calculate, here are the approximate relative atomic masses (atomic weights) of each element involved:
We multiply the atomic mass of each element by the number of atoms present in the formula:
Total Calculation: $28 + 8 + 104 + 112 = 252$
'u' (unified atomic mass unit) is used to express the mass of a single molecule. 'g/mol' is used to express the mass of one mole (Avogadro's number) of those molecules. The numerical value remains exactly the same.
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