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.
Hydrogen can be displaced from a hot alkaline solution by?
Fe
Cu
Ca
Sn
Correct answer is D
Amphoteric oxide react with both acid and alkaline and only amphoteric oxide can displace hydrogen from alkanine solution (al, pb, sn and zinc).
s orbitals
p orbitals
d orbitals
f orbitals
Correct answer is C
No explanation has been provided for this answer.
Chlorine gas is prepared in the laboratory by
adding concentrated hydrochloric acid to solid manganese (IV) oxide
aciding concentrated tetraoxosulphate (VI) acid to solid sodium chloride
dropping concentrated hydrochloric acid onto potassium tetraoxomanganate (VI) crystals
aciding concentrated tetraoxosulphate (VI) acid to hydrochloric acid
Correct answer is A
No explanation has been provided for this answer.
Which of the following is an electrolyte?
Alcohol
Sodium acetate solution
Solid potassium hydroxide
Mercury
Correct answer is B
No explanation has been provided for this answer.
When sugar is dissolved in tea, the reaction is always accomplished by
positive change
negative entropy change
no entropy change
a minimum entropy change
Correct answer is A
The dissolution of sugar in tea is accompanied by positive change in entropy. When there is a change in the state of a substance from solid to liquid, there is an increase in entropy. In general, if a substance changes its structure from a condensed state to a less condensed state, then we say there is an increase in entropy.