Mr (K₂Cr₂O₇) = 39 × 2 + 52 × 2 + 16 × 7 = 294 г/моль
ω (K) = 2 × 39 / 294 × 100% = 26%
ω (Cr) = 2 × 52 / 294 × 100% = 35%
ω (O) = 7 × 16 / 294 × 100% = 38%
Mr (K₂Cr₂O₇) = 39 × 2 + 52 × 2 + 16 × 7 = 294 г/моль
ω (K) = 2 × 39 / 294 × 100% = 26%
ω (Cr) = 2 × 52 / 294 × 100% = 35%
ω (O) = 7 × 16 / 294 × 100% = 38%