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.
In the reaction NH3 + H+ → NH4+, the bond formed results from?
an electron transferred from NH3 + H+
an electron pair donated by NH3
an electron pair equally shared
an electron pair donated by H+
an electron tarnsferred from H+ to NH3
Correct answer is B
The nitrogen atom has a lone pair of electrons that coordinates to the hydrogen cation, which has zero electrons, forming a covalent bond.
Which of the following statements is incorrect?
Calcium reacts with water to form calcium
Magnesium reacts very slowly with water but faster with warm water
Iron will not react with water in the absence of air
Sodium reacts with water
Copper reacts with steam
Correct answer is E
No explanation has been provided for this answer.
deliquescence
hygroscopy
oxidation
efforescence
sublimation
Correct answer is D
No explanation has been provided for this answer.
sodium
chlorine
hydrogen
sodium hydroxide
oxygen
Correct answer is C
During the electrolysis of NaCl using carbon electrodes, hydrogen is usually deposited at the cathode because hydrogen is less reactive and lower than sodium in the electrochemical series(sodium and hydrogen are the two cations in the solution)
Which of the following types of reactions takes place between C2H6 and the halogens?
Substitution
Polymerization
Addition
Saponification
Oxidation
Correct answer is A
Alkanes undergo a substitution reaction with halogens in the presence of light. For instance, in ultraviolet light , methane reacts with halogen molecules such as chlorine and bromine.