281.5 mg/L = 281.5 ppm
| mg/L | ppm |
|---|---|
| 266.5 mg/L | 266.5 |
| 271.5 mg/L | 271.5 |
| 276.5 mg/L | 276.5 |
| 281.5 | 281.5 |
| 286.5 mg/L | 286.5 |
| 291.5 mg/L | 291.5 |
| 296.5 mg/L | 296.5 |
281.5 mg/L = 281.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm