521.5 mg/L = 521.5 ppm
| mg/L | ppm |
|---|---|
| 506.5 mg/L | 506.5 |
| 511.5 mg/L | 511.5 |
| 516.5 mg/L | 516.5 |
| 521.5 | 521.5 |
| 526.5 mg/L | 526.5 |
| 531.5 mg/L | 531.5 |
| 536.5 mg/L | 536.5 |
521.5 mg/L = 521.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm