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.
Which of the following substances increases in mass when heated in air?
Sodium chloride
lodine crystals
magnesium ribbon
copper (ll) oxide
Correct answer is C
No explanation has been provided for this answer.
A substance is said to be hygroscopic if it absorbs?
water from the atmosphere to form a solution
heat from the surrounding
carbon (IV) oxide from the atmosphere
moisture from the atmosphere without dissolving
Correct answer is D
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment,
which is usually at normal or room temperature.
Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution.
Which of the following acids forms normal salts only?
Tetraoxosulphate (VI) acid
Trioxosulphate (IV) acid
Tetraoxophosphate (V) acid
Trioxonitrate (V) acid
Correct answer is D
No explanation has been provided for this answer.
A major factor coonsidered in selecting a suitable method for preparing a simple salt is its
crystalline form
melting point
reactivity with dilute acids
solubility in water
Correct answer is D
No explanation has been provided for this answer.
The gas given off when NH4Cl is heated with an alkali is
H2
CI2
N 2
NH 3
Correct answer is D
No explanation has been provided for this answer.