What is the chemical formula for sodium sulfate?(1) Na2SO4 (2) Na2SO3(3) NaSO4(4) NaSO3

June 2017 NY Regents Chemistry Exam

34 What is the chemical formula for sodium sulfate?

(1) Na2SO4

(2) Na2SO3 (3) NaSO4

(4) NaSO3

Solution: Sodium sulfate is an ionic compound that consists of a metal (sodium) and a polyatomic ion, sulfate. Table E on the Reference Table lists common polyatomic ions with their names, formulas and oxidation numbers. Sulfate is SO4 ^2-. The oxidation number for sodium can be found on the Periodic Table and is +1.

Putting the name together we write both parts with their oxidation numbers and then we criss cross the numbers and make them into subscripts.

Na^+1 SO4^2-

Na2SO4

Answer: 1

Prepare for the Chemistry Regents Exam: HERE

Contact us for chemistry tutoring: HERE