Question

The formula weight of potassium dichromate (k2cr2o7) is __________ amu.

Answer 1

The given compound is $K_{2}Cr_{2}O_{7}$

Each formula unit of $K_{2}Cr_{2}O_{7}$ has 2 mol Potassium (K) atoms, 2 mol Chromium (Cr) atoms and 7 mol Oxygen (O) atoms.

Atomic weight of potassium is 39.0983 amu

Atomic weight of Chromium is 51.9961 amu

Atomic weight of Oxygen is 15.9994 amu.

Therefore the formula weight of $K_{2}Cr_{2}O_{7} =$

$2 * 39.0983 amu + 2 * 51.9961 amu + 7 * 15.9994 amu$

= 294.1846 amu