Chemistry MCQs
Chemistry Objective (Multiple Choice) General Knowledge Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examination.
1. What is the key element used in the batteries of electric vehicles?
[A] Magnesium
[B] Lithium
[C] Sodium
[D] Bromine
Show Answer
Correct Answer: B [Lithium]
Notes:
The primary component for electric vehicle batteries is Lithium, used as Lithium carbonate or Lithium hydroxide. These Lithium-ion batteries have a high power-to-weight ratio, energy efficiency, and thermal stability, leading to their prevalence in electric vehicles. Notably, the boom in EVs has significantly driven the demand for Lithium globally.
2. Which among the following qualities of iron ore is best based upon iron content?
[A] Magnetite
[B] Hematite
[C] Limonite
[D] Siderite
Show Answer
Correct Answer: A [Magnetite]
Notes:
Magnetite, followed by Hematite – Limonite – Siderite
3. What is the primary use of Phenolphthalein in chemistry?
[A] A Solvent
[B] A Dye
[C] A Catalyst
[D] A Detergent
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Correct Answer: B [A Dye]
Notes:
Phenolphthalein is commonly employed as a pH indicator in titrations due to its distinct color change in varying pH levels. At pH 8.2, it appears colorless but turns pink as the pH increases to 10. It is not used as a solvent, catalyst or detergent. It also finds applications in forensic science for detecting latent blood stains.
4. Which among the following is an ionic solid?
[A] Diamond
[B] Dry ice
[C] Table salt
[D] All are ionic solids
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Correct Answer: C [Table salt]
Notes:
One important character of Ionic solids is that they readily get dissolved in water
5. Pyrolusite, Braunite, Psilomelane, Rhodochrosite are the ores of which among the following metals?
[A] Manganese
[B] Aluminium
[C] Copper
[D] Manganese and Copper
Show Answer
Correct Answer: A [Manganese]
Notes:
Pyrolusite, Braunite, Psilomelane, and Rhodochrosite are all ores of Manganese. Pyrolusite is one of the most important ores due to its high manganese content. Braunite, although a significant ore, its manganese content is less than Pyrolusite. Psilomelane and Rhodochrosite also contribute as minor ores.
6. What is the general trend for ionization enthalpies of alkali metals as we move down the group?
[A] it increases
[B] it decreases
[C] it is same for all
[D] None
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Correct Answer: B [it decreases]
Notes:
The ionization enthalpies of the alkali metals are considerably low and decrease down the group from Li to Cs.
7. Which of the following metal is alloyed with pure gold to make gold ornaments?
[A] Silver
[B] Copper
[C] Zinc
[D] All of the above
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Correct Answer: D [All of the above]
Notes:
24 carat gold is considered to be the purest form of gold but it is too soft to be made into jewellery. It is alloyed with metals like zinc, cadmium, silver or copper to make it hard.
8. Which of the following is not a mixture?
[A] Ocean water
[B] Table salt
[C] Air
[D] Soil
Show Answer
Correct Answer: B [Table salt]
Notes:
The composition of a mixture is variable whereas it is fixed for a compound. Table salt i.e. Sodium chloride is a compound and not a mixture.
9. Which of the following is correct about Solder?
[A] It is an alloy of lead and tin
[B] It is used for welding electrical wires together
[C] It has a low melting point
[D] All of the above
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Correct Answer: D [All of the above]
Notes:
Solder is an alloy of lead and tin (Pb and Sn). It has a low melting point and is used for welding electrical wires together.
10. Which of these is an ore of Aluminium?
[A] Corundum
[B] Kieserite
[C] Pitch blende
[D] All of the above
Show Answer
Correct Answer: A [Corundum]
Notes:
Corundum is an ore of Aluminium. It is a crystalline form of aluminium oxide. Kieserite is an ore of Magnesium and Pitch blende is an ore of Uranium.
