The most common process in the extraction of metals from their ore is
catalysis
electrolysis
oxidation
reduction
Correct answer is D
No explanation has been provided for this answer.
Which of the following gases is used to retard the vaporization of the filament in a light bulb?
Argon
Helium
Hydrogen
Oxygen
Correct answer is A
No explanation has been provided for this answer.
The purity of a solid sample can best be determined by its?
boiling point
melting point
conductivity
solubility
Correct answer is B
- The presence of impurities in a substance results in a lower melting point due to a process called melting point depression.
- That implies a pure solid has a SHARP melting point which is of the standard value when compared.
The production of biogas from the fermentation of waste materials is an example of
combustion
incineration
refining
recycling
Correct answer is D
No explanation has been provided for this answer.
Which of the following organic compounds could be represented by the empirical formula CH2O?
Ethanal
Ethane
Ethanol
Ethanoic acid
Correct answer is D
No explanation has been provided for this answer.