Question

The tests below were carried out on a solution containing ions of the metal X.

add sodium chloride solution- no change
add sodium sulfate solution- no change
add sodium hydroxide solution-
a precipitate was formed, soluble
in excess of the hydroxide
What is metal X?
A calcium
B iron
C lead
D zinc

Answer 1

Please explain as well.

Answer 2

Metal X can't be lead, since it didn't precipitate with the chloride ion.
Metal X can't be calcium, since it didn't precipitate with the sulfate ion.
Both iron and zinc are soluble in sulfates.
Both lead and zinc hydroxides will become soluble in an excess of hydroxide, but metal X can't be lead because it still failed test #1.

Metal X has to be zinc.

Answer 3

must be zinc