General Science Questions (MCQs) for Competitive Examinations
General Science Multiple choice questions for GK paper in SSC, NDA, CDS, UPSC, UPPSC and State PSC Examinations. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. Which iron ore contains the highest percentage of iron content?
[A] Hematite
[B] Siderite
[C] Magnetite
[D] Limonite
Show Answer
Correct Answer: C [Magnetite]
Notes:
Magnetite (Fe3O4) typically contains about 70% iron by weight. It is black in color and strongly magnetic. Hematite (Fe2O3) contains about 60–70% iron. Limonite contains 35–50% iron. Siderite (FeCO3) contains about 48% iron. Magnetite is widely mined due to its high iron concentration compared to other ores.
2. Who among the following scientists had discovered Radium?
[A] Marie Sklodowska-Curie and Pierre Curie
[B] André-Louis Debierne
[C] Kasimir Fajans
[D] Oswald Helmuth Göhring
Show Answer
Correct Answer: A [Marie Sklodowska-Curie and Pierre Curie ]
Notes:
Radium is a chemical element with the symbol Ra and atomic number 88. Radium was discovered by Marie Sklodowska Curie, a Polish chemist, and Pierre Curie, a French chemist, in 1898.
3. Which of the following are used as chemical agents in war?
- Mustard Gas
- Phosgene
- Sarin
- VX
Select the correct option from codes given below:
[A] 1 & 3 Only
[B] 1, 3 & 4 Only
[C] 2 & 4 Only
[D] 1, 2, 3 & 4
Show Answer
Correct Answer: D [ 1, 2, 3 & 4]
Notes:
Chemical weapons are called “poorman’s bomb”. These cause catastrophic damage, and are easy to produce. Sarin is a colorless and odourless agent, and is extremely potent. It was used in Damascus in 2013. Mustard Gas is possibly the most commonly used chemical agent and gets its name from the distinctive odour of rotten mustard. It is less potent and usually only 5 to 10 percent people exposed to it usually die. It was widely used during Second World War. VX is a nerve agent which is odourless and appears as brownish oily substance.
4. Which of the following elements is present in heavy water?
[A] Heavy Oxygen
[B] Heavy Hydrogen
[C] Heavy Chlorine
[D] Heavy Nitrogen
Show Answer
Correct Answer: B [Heavy Hydrogen ]
Notes:
Heavy water is water that contains heavy hydrogen or deuterium. Deuterium differs from the hydrogen usually found in water, protium, in that each atom of deuterium contains a proton and a neutron. Heavy water may be deuterium oxide, D2O or it may be deuterium protium oxide, DHO.
5. Which among the following metals is the hardest metal?
[A] Platinum
[B] Gold
[C] Iron
[D] Tungsten
Show Answer
Correct Answer: D [Tungsten]
Notes:
Tungsten has the highest tensile strength of any natural metal, with an ultimate strength of 1510 megapascals. Tungsten has the highest melting point (3422 °C, 6192 °F), lowest vapor pressure (at temperatures above 1650 °C, 3000 °F).
6. Biofortification is a ____:
[A] Method of plant breeding for disease resistance
[B] Method of developing resistance to insect pests
[C] Method of breeding crops to increase their nutritional value
[D] Strategy to combat unwanted nutrients in plants
Show Answer
Correct Answer: C [Method of breeding crops to increase their nutritional value]
Notes:
Biofortification is the breeding crops to increase their nutritional value. This can be done either through conventional selective breeding or genetic engineering. Biofortification differs from ordinary fortification because it focuses on making plant foods more nutritious as the plants are growing, rather than having nutrients added to the foods when they are being processed.
7. The wing of a bat and the wing of a bird are the examples of ____ limbs:
[A] Heterogeneous
[B] Homogenous
[C] Homologous
[D] Analogous
Show Answer
Correct Answer: D [Analogous]
Notes:
The wings of insects, bats and birds, that evolved independently in each lineage separately after diverging from an ancestor without wings, are examples of analogous organs. Analogous organs are the opposite of homologous organs, which have similar functions but different origins.
8. Which of the following cell organells are present only in plant cell?
[A] Lysosomes
[B] Plastids
[C] Mitochondria
[D] Cell membrane
Show Answer
Correct Answer: B [Plastids]
Notes:
The plastid is a major double-membrane organelle found in the cells of plants. Plastids are the site of manufacture and storage of important chemical compounds used by the cell. Plastids often contain pigments used in photosynthesis, and the types of pigments present can change or determine the cell’s colour.
9. Vermicomposting is done by ____:
[A] Bacteria
[B] Worms
[C] Fungus
[D] Animals
Show Answer
Correct Answer: B [Worms]
Notes:
Vermicomposting is the process of using worms also called red worms and micro-organisms to turn kitchen waste into black, earthy-smelling, nutrient-rich humus. Vermicompost is an excellent, nutrient-rich organic fertilizer and soil conditioner.
10. Which of the following vitamins help in the absorption of calcium?
[A] Vitamin A
[B] Vitamin B
[C] Vitamin C
[D] Vitamin D
Show Answer
Correct Answer: D [Vitamin D]
Notes:
Vitamin D is essential in helping the body absorb and use calcium; in fact, the body cannot absorb calcium at all without some vitamin D. Vitamin D helps our intestines absorb calcium from the food we eat and helps build stronger bones.