661.5 mg/L = 661.5 ppm
| mg/L | ppm |
|---|---|
| 646.5 mg/L | 646.5 |
| 651.5 mg/L | 651.5 |
| 656.5 mg/L | 656.5 |
| 661.5 | 661.5 |
| 666.5 mg/L | 666.5 |
| 671.5 mg/L | 671.5 |
| 676.5 mg/L | 676.5 |
661.5 mg/L = 661.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm