721.5 mg/L = 721.5 ppm
| mg/L | ppm |
|---|---|
| 706.5 mg/L | 706.5 |
| 711.5 mg/L | 711.5 |
| 716.5 mg/L | 716.5 |
| 721.5 | 721.5 |
| 726.5 mg/L | 726.5 |
| 731.5 mg/L | 731.5 |
| 736.5 mg/L | 736.5 |
721.5 mg/L = 721.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm