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.
According to the kinetic theory an absence in temperature causes the kinetic energy of particles to
decrease
increase
remain constant
be zero
Correct answer is D
No explanation has been provided for this answer.
A difference between chemical and physical change is that in a chemical change
oxygen is consumed
heat is supplied
the reversible process occurs
a new substance is formed
Correct answer is D
In chemical change a new substance is formed while in physical change no new substance is formed. Options A,B,C are all properties of a physical change
The furring of kettles is caused by the presence of what compound in water?
calcium tetraoxosulphate (IV)
calcium hydrogentrioxocarbonate (IV)
calcium hydroxide
calcium trioxocarbonate (IV)
Correct answer is D
Calcium hydrogen carbonate, often present in temporary hard water, is boiled in a kettle to remove the hardness. In the process, a scale forms on the inside of the kettle in a process known as furring of kettles. This scale is composed of calcium carbonate.
Which of the following results in the fall of acid rain?
oxide of lead
particulate matter
oxides of sulphur
gaseous hydrocarbon
Correct answer is C
Oxide of sulphur is formed as a result of acid rain. Options A,B, D are not formed as a result of the pressure of acid
Detergents are manufactured with straight hydrocarbon chains, is to make them
soluble
biodegradable
cheaper
foamy
Correct answer is B
Biodegradable because the straight hydrocarbons are natural and slightly soluble in water. Options A,C,D do not have strength hydrocarbon chains and they could harm the environment if they are made with the detergent