251.5 mg/L = 251.5 ppm
| mg/L | ppm |
|---|---|
| 236.5 mg/L | 236.5 |
| 241.5 mg/L | 241.5 |
| 246.5 mg/L | 246.5 |
| 251.5 | 251.5 |
| 256.5 mg/L | 256.5 |
| 261.5 mg/L | 261.5 |
| 266.5 mg/L | 266.5 |
251.5 mg/L = 251.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm