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.
The high solubility of ethanol in water is due to?
its low boiling point.
its low freezing point.
its covalent nature
hydrogen bonding
Correct answer is D
Ethanol is an alcohol that is soluble in water. This is because of the hydroxyl group (−OH) in the ethanol that is able to form hydrogen bonds with the water (H2O) molecules.
Calcium trioxocarbonate ( iv ) chips a 20°C
CalcIum trioxocarbonate (IV) chips at 40°C
Calcium trioxocarbonate (IV) powder at 20'C
Calcium trioxocarbonate (IV) powder at 40'C
Correct answer is A
- Increasing the surface area of a reactant increases the frequency of collisions and increases the reaction rate.
- Chips have a lower surface area compared to powder, so it accounts for the slowest
[Ag = 108, IF = 96,500 C ]
432g
108g
54g
27g
Correct answer is D
Ag + e → Ag
1 mole of Ag+ = 108
i.e 108 X 1 X 96500
But, 24,125C will produce ( 108 X 24,125 ) / ( 1 X 96500 )
Ag = 27g
What quantity of electrons is lost when one mole of iron (II) ions is oxidized to iron (III) ?
0 mole
3 moles
I mole
2 moles
Correct answer is B
Fe^2^+ → Fe^3^+
The pale green Fe2+ is oxidized to orange Fe3+ because it loses an electron.
Which or the following products could be formed during incomplete combustion of a hydrocarbon.
i.Carbon ii. Hydrogen III. Carbon (Il) oxide
I only
I and II only
I and III only
II and III only
Correct answer is C
Incomplete combustion occurs when the supply of air or oxygen is poor. Water is still produced, but carbon monoxide and carbon are produced instead of carbon dioxide. The carbon is released as soot.