| ITEM | STANDARD |
| Appearance | White or pale yellowish powder or granule |
| Purity | ≥ 95 |
| PH value (3% aqueous solution) | 7.0-8.5 |
| Color of solution (APHA) | ≤ 40 |
| Water | ≤ 29.0 |
| Arse-nic % | ≤ 0.0002 |
| Free ascorbic acid % | ≤ 0.5 |
| Free phos-phoric acid % | ≤ 1.0 |
| Free phos-phoric acid % | ≤ 0.35 |
| Heavy Metals (Pb) % | ≤ 0.001 |
