Sodium Hexametaphosphate Concentration Greater Than99 CAS Number 50813-16-6 Chemical Formula Na(x+2) Px O(3x+1) x = 6 to 21 Chemical Container Material Plastic Chemical Container Type Bottle Chemical Grade Purified Chemical Container Size 1 lb Chemical Family Type Analytical Reagents Shelf Life 1 yr Standards ASTM D422 AASHTO T88.