Chemistry MCQs
Chemistry Objective (Multiple Choice) General Knowledge Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examination.
1. Which of the following is an alkaline earth metal?
[A] Pottasium
[B] Lead
[C] Copper
[D] Calcium
Show Answer
Correct Answer: D [Calcium ]
Notes:
The six elements in column 2 of the Periodic table are called Alkaline Earth Metals. These include Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra).
2. Which among the following element is an essential constituent of acids?
[A] Nitrogen
[B] Hydrogen
[C] Oxygen
[D] Helium
Show Answer
Correct Answer: B [Hydrogen]
Notes:
Acids are molecules that are able to donate proton or H+ thus, hydrogen is essential for acids. However, there are exception to this such as Bronsted acids. A Bronsted acid is an acid which can accept an electron pair, but does not have a proton (H+) to donate. Examples of such acids are Aluminum Chloride (AlCl3), Boron Trifuoride (BF3).
3. Which among the following scientists had discovered Radium?
[A] Marie and Pierre Curie
[B] Andre-Louis Debierne
[C] Kasimir Fajans
[D] Oswald Helmuth Gohring
Show Answer
Correct Answer: A [Marie and Pierre Curie]
Notes:
Radium(Ra) with atomic number 88 was discovered by Marie and Pierre Curie in 1898 as Radium Chloride. However, it was Radium was isolated in its metallic state by Marie Curie and André-Louis Debierne through the electrolysis of radium chloride in 1911.
4. Which of these is not considered an ore?
[A] Chalcopyrite
[B] Sphalerite
[C] Cinnabar
[D] Andesite
Show Answer
Correct Answer: D [Andesite]
Notes:
Andesite is an igneous volcanic rock with intermediate composition and is not used as an ore. Chalcopyrite is a major copper ore, sphalerite is the primary ore of zinc, and cinnabar is the main ore of mercury. Andesite mainly consists of plagioclase, pyroxene, and amphibole minerals and forms in volcanic arcs associated with subduction zones.
5. What is the number of naturally occurring Halogens in the periodic table?
[A] 3
[B] 4
[C] 5
[D] 6
Show Answer
Correct Answer: C [5]
Notes:
fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At)
6. Buckeyballs are basically the allotropes of _________?
[A] Carbon
[B] Sulfur
[C] Phosphorus
[D] Calcium
Show Answer
Correct Answer: A [Carbon]
Notes:
Buckeyballs, or fullerenes, are allotropes of carbon. Discovered in 1985, they consist of 60 carbon atoms arranged in a spherical shape, resembling a soccer ball. This unique structure contributes to their remarkable properties, including high strength and electrical conductivity. Fullerenes are part of a broader class of carbon allotropes, which also includes graphite and diamond.
7. If a Hydrogen atom is removed from a hydrocarbon of Benzene group, the remaining residue is called _________?
[A] Alkyl
[B] Aryl
[C] Arene
[D] Azene
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Correct Answer: B [Aryl]
Notes:
The correct answer is Aryl. In organic chemistry, when a hydrogen atom is removed from a benzene ring (a hydrocarbon), the remaining structure is referred to as an aryl group. Aryl groups are derived from aromatic compounds, specifically those containing a benzene ring. For example, when a hydrogen is removed from toluene (methylbenzene), the resulting aryl group is called a tolyl group. Aryl groups are important in various chemical reactions and are foundational in the synthesis of many organic compounds.
8. Ilmenite, found in Indian coastal sands, is an ore of which element?
[A] Tungsten
[B] Titanium
[C] Gallium
[D] Tin
Show Answer
Correct Answer: B [Titanium]
Notes:
Ilmenite is a titanium-iron oxide mineral with the formula FeTiO3. India holds about 37% of global ilmenite reserves, primarily along the peninsular coastal regions. Ilmenite is the primary source of titanium, used in aerospace, chemical, and medical industries. The Geological Survey of India ranks ilmenite among the most abundant heavy minerals in Indian beach placers. Titanium extraction from ilmenite is commercially viable.
9. Which of the following laws is used as a rule to predict the solubility of gases in metals?
[A] Dalton’s Law
[B] Sievert’s law
[C] Graham’s law
[D] Henry’s law
Show Answer
Correct Answer: B [ Sievert’s law]
Notes:
Sievert’s law is used as a rule in physical metallurgy to predict the solubility of gases in metals.
10. Which of the following chemicals is also known as "butter of tin"?
[A] Stannic chloride
[B] Sodium perborate
[C] Potassium nitrate
[D] Magnesium hydroxide
Show Answer
Correct Answer: A [ Stannic chloride]
Notes:
“Butter of Tin” is also known as tin tetrachloride pentahydrate. It is called “butter of tin” because of its physical appearance. Its chemical formula is SnCl4*5H2O or [SnCl4 (H2O)]*3H2O.