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 heat required to raise the temperature of the body by 1k is called?
Specific heat
Thermal capacity
Water equivalent
None of the above
Correct answer is B
Heat capacity or thermal capacity: The amount of heat to be supplied to an object to produce a unit change in its temperature(1k).
The most abundant rare gas in the atmosphere is?
He
Ne
Ar
Xe
Correct answer is C
The most abundant naturally occurring gas is Nitrogen (N2), which makes up about 78% of air. Oxygen (O2) is the second most abundant gas at about 21%. The inert gas Argon (Ar) is the third most abundant gas.
Argon is the most abundant rare gas in the atmosphere. It is represented by the symbol Ar. The atomic number of Ar is 18.
The inherited traits of an organism are controlled by?
RNA molecules
Nucleotides
DNA molecules
Enzymes
Correct answer is C
DNA now has three distinct functions—genetics, immunological, and structural—that are widely disparate and variously dependent on the sugar phosphate backbone and the bases.
220g of carbon dioxide contains ----- moles
5
6
3
4
Correct answer is A
One mole of carbon dioxide molecules has a mass of 44.01 g,
: 5 mole of carbon dioxide molecules has a mass of 220g
The mass of one Avogadro number of helium atoms is?
1.00gram
4.00gram
8.00gram
6.00gram
Correct answer is B
Avogadro's number is an absolute number: there are 6.022×10\(^23\) elementary entities in 1 mole.
helium has a molar mass of 4.0 grams per mole. So one mole of helium has a mass of 4.0 grams.