Question

Sodium pyrophosphate has the chemical formula
A. $N{a_2}{P_2}{O_7}$
B. $N{a_3}P{O_4}$
C. $N{a_4}{P_2}{O_7}$
D. $N{a_3}P{O_3}$

Answer 1

Tetra sodium Pyrophosphate, also known as Sodium Pyrophosphate, is an odourless, white powder or granular solid. It is used in household and industrial cleaning compounds, as a water softener, metal cleaner and food additive, and for oil well drilling. Sodium pyrophosphate has the molecular Formula of $N{a_4}{P_2}{O_7}$. It has the Average mass of 265.902 Da and has the Monoisotopic mass of 265.871002 Da.

Complete step by step answer:
Except where otherwise noted, data are given for materials in their standard state (at $25^\circ C$ $\left[ {77^\circ F} \right],100kPa$ ). Sodium pyrophosphate, also called tetra sodium pyrophosphate or TSPP, is an inorganic compound with the formula $N{a_4}{P_2}{O_7}$. The related substance sodium pyrophosphate decahydrate $(N{a_4}{P_2}{O_7}.10{H_2}O)$ occurs as colourless transparent crystals. Loses its water when heated to $93.8^\circ C$.
Sodium pyrophosphate is produced by the reaction of furnace grade phosphoric acid with sodium carbonate to form disodium phosphate, which is then heated at $450^\circ C$ to form sodium pyrophosphate. The chemical equation can be shown as below:
$2{\text{ }}N{a_2}HP{O_4} \to {\text{ }}N{a_4}{P_2}{O_7} + {\text{ }}{H_2}O$
Thus, we know that the chemical formula of Sodium pyrophosphate is $N{a_4}{P_2}{O_7}$.

Therefore, the correct answer is option (C).

Note: Sodium Pyrophosphate is a synthetic ingredient that can be used as an acid regulator, sequestrate, protein modifier, coagulant, and a dispersing agent in food with the European food additive number E450(iii). It is gluten free and vegan. It is the anti-tartar ingredient in Crest Whitening Expressions. They are normal components of human body fluids, are used in many foods, and they have a GRAS (Generally Recognized as Safe) rating from the FDA.