Question

Nitrate=NO3^-
Hydrogen Carbonate = HCO3^-

what is 3 in NO3^-
how did it came?
plz help me!​

Answer 1

Infobox references. Nitrate is a polyatomic ion with the chemical formula NO − 3. Salts containing this anion are called nitrates. Nitrates are common components of fertilizers and explosives.

Answer 2

Nitrate and nitrite can also be produced as a result of nitrification in source water or distribution systems. In general, the most important source of human exposure to nitrate and nitrite is through vegetables (nitrate and nitrite) and through meat in the diet (nitrite is used as a preservative in many cured meats).