Are all standard solutions primary standard solutions or not?? Why?

What are the spectator ions in 2h+ + so42- + ca2+ + 2r → caso4 + 2h+ + 21?

How can the periodic table be used to predict the behavior of elements?

If a straight-chain hydrocarbon is a gas at room temperature, how many carbon atoms will it have? a. 6 carbon atoms b. 12 carbon atoms c. 24 carbon atoms d. 3 carbon atoms