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 ONE of the following statements is true?
All alkali metals salts dissolves with dissociation in water
Most ionic substances are easily vaporized
Ionic substances exist only as liquid
Non-ionic substances are good electrolytes
Nitrogen exists in a trivalent state in ammonium salts
Correct answer is A
All alkali metal salts are soluble in water.
When exposed to air, it slowy changes to liquid
its solution in water conducts electricity
Its solution in water, on evaporationm gives a white solid
Its solution in water liberates hydroge when in contact with aluminium metal
Its oxide, when stronlgy heated, regenerates the elements X
Correct answer is A
No explanation has been provided for this answer.
Chlorine, bromine and iodine resemble each other in that all?
dissolve in alkalis
react violently with hydrogen without heating
displace each other from solutions of their salts
are gases
are liquids
Correct answer is A
Alkali metals tend to lose one electron and form ions with a single positive charge.
They form ionic compounds (salts) in reaction with the halogens (alkali halides)
The boiling point of water is higher than that of methanol because?
water is oxide while methanol is an alcohol
inter molecular forces in water are stronger than those in methanol
water is an inorganic compound while methanol is organic
water is an ionic compound while methanol is a covalent compound
water is more reactive than methanol
Correct answer is B
No explanation has been provided for this answer.
8.0 g
4.0 g
0.8 g
0.4 g
Correct answer is D
let the divalent metal be Q
Q + 2HCl → QCl2 + H2
1mole of Q liberated 1 mole of Hydrogen gas ( one mole of any gas at STP has a volume of 22400cm^3 or 22.4dm^3 )
40 → 22400cm^3
? → 224cm^3
mass of Q = \(\frac{ 40 \times 224}{22400}\)
mass of Q = 0.4g.