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. The exceptionally low melting point of mercury can be explained on the basis of which of the following explanations?
1. Mercury has completely filled-up atomic orbitals
2. In mercury, the binding energy of outer electrons (towards nucleus) is highest and no electron is available to participate in metallic bond formation
Choose the correct option from the codes given below:
[A] Only 1 is correct
[B] Only 2 is correct
[C] Both 1 & 2 are correct
[D] Neither 1 nor 2 is correct
Show Answer
Correct Answer: C [ Both 1 & 2 are correct]
Notes:
Mercury belongs to the zinc group of elements in the periodic table, which comprises zinc, cadmium and mercury. They all have completely filled-up atomic orbitals. It becomes difficult to knock out these electron(s) from their orbitals and form metallic bonds. With its filled shell electron configuration it is very reluctant to form bonds even with other mercury atoms.
2. As per the Mohs scale of mineral hardness, which of the following are soft metals?
- Gold
- Copper
- Diamond
- Thorium
Select the correct option from codes given below:
[A] 1 & 4 Only
[B] 1, 2 & 4 Only
[C] 2 & 4 Only
[D] 1, 2, 3 & 4
Show Answer
Correct Answer: B [ 1, 2 & 4 Only]
Notes:
As per the Mohs scale of mineral hardness, the soft metals are: Lead, gold, silver, tin, zinc, aluminium, thorium, copper, brass and bronze. Diamond is one of the hardest known metals on earth.
3. What is the 4th state of matter?
[A] Bose-Einstein condensates
[B] Plasma
[C] Gas
[D] Liquid
Show Answer
Correct Answer: B [Plasma]
Notes:
Plasma is considered a distinct “fourth state of matter. A plasma is a hot ionized gas consisting of approximately equal numbers of positively charged ions and negatively charged electrons. The characteristics of plasmas are significantly different from those of ordinary neutral gases.
4. 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).
5. 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.
6. If waste materials contaminate the source of drinking water, which of the following diseases will spread?
[A] Typhoid
[B] Malaria
[C] Anaemia
[D] Scurvy
Show Answer
Correct Answer: A [Typhoid]
Notes:
Typhoid is a common worldwide bacterial disease transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica subsp. enterica, serovar Typhi.
7. What is thick vein present in the middle of the leaf called?
[A] Leaf venation
[B] Parallel venation
[C] Midrib
[D] Reticulate
Show Answer
Correct Answer: C [Midrib]
Notes:
A thick vein seen in the middle of the leaf is called the midrib. Pinnately veined leaves have one large central vein, called the midrib, which extends from the base of the blade to its tip. Other large veins branch off on each side of the midrib. The leaves of beech, birch, and elm trees have such a vein pattern.
8. In the context of agriculture, the term barani refers to ____:
[A] Rain-fed farming
[B] Irrigated farming
[C] Mixed farming
[D] Dry farming
Show Answer
Correct Answer: A [Rain-fed farming]
Notes:
Barani area are traditionally rain-fed areas. These are any low rain area where the rain-fed dry farming is practiced. Bagar tract, the dry sandy tract of land on the border of Rajasthan state adjoining the states of Haryana and Punjab, is an example of Barani land.
9. The pigment that gives human skin, hair and eyes their colour is called ____:
[A] Quinacridone
[B] Alizarin
[C] Melanin
[D] Phthalocyanine
Show Answer
Correct Answer: C [Melanin ]
Notes:
The pigment that gives human skin, hair, and eyes their color. Dark-skinned people have more melanin in their skin than light-skinned people have. Melanin is produced by cells called melanocytes. Everyone has the same number of melanocytes, but some people make more melanin than others.
10. In which of the following multiple epidermis is found?
[A] Boerhaavia
[B] Nerium
[C] Amaranthus
[D] Helianthus
Show Answer
Correct Answer: B [Nerium]
Notes:
It is assumed that protodermal cells divide periclinally in certain cases to form multiseriate or multiple epidermis. The multiple epidermis is found in some organs like roots of orchids (Vanda), leaves of Ficus, Nerium, Piperomia, etc. In Nerium, it is found on both surfaces.
