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.
1s2, 2s2, 2p6, 3s2, 3p6, 3d7, 4s2
An element with the electronic configuration above is a
non-metal
metal
transition element
group two element
Correct answer is C
No explanation has been provided for this answer.
The method that can be used to convert hard water to soft water is
chlorination
passage over activated charcoal
the use of an ion-exchange resin
aeration
Correct answer is C
No explanation has been provided for this answer.
water vapour
oxygen
carbon (IV) oxide
rare gases
Correct answer is D
The correct answer is rare gases because when nitrogen is obtained from air, \(CO_2\) and \(O_2\) are removed by passing air through caustic soda and heated copper turnings respectively.
However, the nitrogen obtained this way contains about 1% by volume of rare gases as impurities, these rare gases make it denser than nitrogen obtained from nitrogen compounds like ammonia, etc
electron affinity
ionization energy
activation evergy
electronegativity
Correct answer is B
No explanation has been provided for this answer.
In which of the following are water molecules in the most disorderly arrangement?
Ice at -10°C
Ice at 0°C
Water at 100°C
Steam at 100°C
Correct answer is D
The gaseous state of matter has the most disorderly arrangement of particles. Hence, steam (water in gaseous form) is the most disorderly arrangement on the list.