1. An element of an inorganic compound found in nature and contains metal is known as _________.
A. Mineral
B. Ore
C. Both (a) and (b)
D. None of these
ANSWER:A.Mineral
SOLUTION : Minerals are inorganic compounds or elements that contain metals and occur naturally in the earth’s crust. They are usually solid, crystalline, and form by geological processes. Minerals have a fixed chemical composition and can be found in pure form or as an alloy.
2. A chemical process of extracting a metal from its ore is known as ________.
A. Mineralogy
B. Metallurgy
C. Liquation
D. None of the above
ANSWER:B.Metallurgy
SOLUTION:The process of extracting metals from their ores is called metallurgy. The specific method used depends on the type of ore and the impurities it contains.
3. A mineral from which the metal is extracted economically is known as _________.
A. Matrix
B. Gangue
C. Ore
D. None of these
ANSWER : C.Ore
SOLUTION: A mineral from which metal can be extracted economically is called an ore. Ores are minerals found in the Earth’s crust that contain metal compounds in high enough concentrations to be extracted profitably. All ores are minerals, but not all minerals are ores.
4. An unwanted earthly material associated with tin ore as impurity is known as __________.
A. Gangue
B. Flux
C. Froth
D. None of these
ANSWER: A.Gangue
SOLUTION:The unwanted earthly materials present in an ore are known as gangue.
5. The process used to convert impure alumina to pure alumina is __________.
A. Roasting
B. Electrolytic refining
C. Purification
D. Baeyer’s process
ANSWER: D.Baeyer’s process
SOLUTION: Baeyer’s process is used to convert impure alumina to pure alumina.
6. Aluminium powder is used in thermite welding because _______.
A. It is a strong reducing agent
B. It is strong oxidising agent
C. It is corrosion resistant
D. It is a good conductor of heat
ANSWER:A. It is a strong reducing agent
SOLUTION:It is a strong reducing agent. It is a strong oxidizing agent. It is corrosion resistant.
7. Metals aluminium and copper present in the alloy ______.
A. Solder
B. Brass
C. Bronze
D. Duralumin
ANSWER:D.Duralumin
SOLUTION :
Rolled gold: Rolled gold is an alloy of Copper and Aluminium. It is used for making cheap ornaments. An alloy is a mixture of two or more metals.
8. In electrolytic refining of metals the impure metal is made _______.
A. Cathode
B. Salt bridge
C. Anode
D. Electrode
ANSWER: C.Anode
SOLUTION:In electrolytic refining the impure metal is made as anode and the pure metal is made as cathode.
9. The method used for refining of aluminium is ____________.
A. Hall’s Process
B. Bayaer’s Process
C. Hoopes Process
D. All of the above
ANSWER:C.If its hydrogen/hydrogen compound content is zero
SOLUTION:Therefore, the purification of aluminum by electrolytic refining is known as Hoope’s process.
10. Biogas is produced by anaerobic fermentation of biological materials. The main constituent of biogas is ________.
A. Propane
B. Ethene
C. Butane
D. Methane
ANSWER: D.Methane
SOLUTION:
Biogas is produced under anaerobic conditions; the process is denominated as anaerobic digestion. The major constituent of biogas is methane (55-70%), CO2 (30-45%) and some traces of gases such as H2S and ammonia.