How many total number of all the elements present in mole of (NH4)2 Cr2O7? Thanks a lot.

1 Answer
Nov 19, 2016

We use Avogadro's number, NA=6.022×1023mol1, to quantify the numbers of individual atoms in a mole, i.e. a 252.07 g mass of (NH4)2Cr2O7.......

Explanation:

In such a mass, there are 2×NA nitrogen atoms, and

8×NA hydrogen atoms, and

2×NA chromium atoms, and

7×NA oxygen atoms.

Here we use NA as a counting number, i.e. as we would use the number 10, or a million, or a dozen.