Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
Detergents are more advantageous than soaps in hard water districts because
on treatment with hard water they either form soluble calcium salts or do not react with calcium ion
on treatment with hard water they form soluble calcium salts
on treatment with hard water they form sodium salts
on treatment with hard water they are converted into soaps
on treatment with hard water they form more lather than soaps does
Correct answer is A
No explanation has been provided for this answer.
N2O
NO
NO2
NaNO3
NH3
Correct answer is C
No explanation has been provided for this answer.
Cu(OH)2
CuSo4.5H2O
(NH4)2SO4
Cu(NH3)4(OH)2
CuSO4.(NH4)2SO4.2H2O
Correct answer is D
\(CuSO_4+2NH_4OH→(NH_4)_2SO_4+Cu(OH)_2\)(pale−blue)
The pale blue precipitate of copper hydroxide dissolves in excess of ammonium hydroxide forming tetraamine copper [II] sulphate, an azure blue(deep blue) soluble complex salt.
\(Cu(OH)_2+(NH_4)_2SO_4+2NH_4OH→[Cu(NH_3)_4]SO_4+4H_2O\)
silver nitrates solution, a white precipates insoluble in dilute HNO3
barium chloride solution, a white precipitate insoluble in dilute H2SO4
barium chloride solution, a white precipitate soluble in dilute HCl
barium chloride solution a white precipitate soluble in dilute ammonia
barium chloride solution a white precipitate insoluble in dilute HCl
Correct answer is E
Sulfate ions in solution are detected using barium chloride solution.
The test solution is acidified using a few drops of dilute hydrochloric acid, and then a few drops of barium chloride solution are added.
A white precipitate of barium sulfate forms if sulfate ions are present.
chlorine
aluminium
silicon
magnesium
sodium
Correct answer is B
No explanation has been provided for this answer.