Question

What is the molar mass of (NH4)2Cr207 (Ammonium dichromate)?

Answer 1

The molar mass of ammonium dichromate is `"252.06 g/mol"`

Explanation:

To calculate the molar mass of a compound, you multiply the subscripts of each element times its molar mass (atomic weight in g/mol).

`"(NH"_4)_2"Cr"_2"O"_7"`

When there is no written subscript, it is understood to be `1`. Also, when elements are enclosed in parentheses, the subscripts on the inside are multiplied by the number outside the parentheses.

Molar Masses of the Elements
Nitogen: `"14.007 g/mol"`
Hydrogen: `"1.00794 g/mol"`
Chromium: `"51.9961 g/mol"`
Oxygen: `"15.999 g/mol"`

Molar Mass of Ammonium Dichromate
`(2xx14.007)+(8xx1.00794)+(2xx51.9961)+(7xx15.999)="252.06 g/mol"`