1.Potassium permanganate is used to purify water. Which among the following properties of Potassium permanganate helps in this work?

[A] sterilizing
[B] oxidizing
[C] reducing
[D] leaching

 

Correct Answer: B [oxidizing]

Notes:
Potassium permanganate is a point-of-entry treatment method that oxidizes dissolved iron, manganese, and hydrogen sulfide into solid particles that are filtered out of the water. It can also be used to control iron bacteria growth in wells.

2.Which among the following was the first artificially produced element?

[A] Neptunium
[B] Ununbium
[C] Technetium
[D] none of the above

 

Correct Answer: C [Technetium]

Notes:
Technetium was the first artificially produced element. It was isolated by Carlo Perrier and Emilio Segrè in 1937. Technetium was created by bombarding molybdenum atoms with deuterons that had been accelerated by a device called a cyclotron.

3.Many a times, we read in newspapers that detergents are used in making the adulterated milk. Why detergents are used in Milk adulteration ?

[A] To dissolve the fats in water
[B] To neutralize the acidity of the solution
[C] To replace the milk solids
[D] To preserve it during transportation

 

Correct Answer: A [ To dissolve the fats in water]

Notes:
Detergent has been found to be the youngest entry among the list of adulterants in milk; used for the emulsification of externally added vegetable fat. The other ingredients being used for preparing milk like formulation are urea, salt, soda, sucrose, vegetable oils, skim milk powder, water etc. The liquid thus formed has the similar appearance as of genuine milk (colour and consistency) and found to be used for adulteration. Generally synthetic milk is prepared by adding detergent to emulsify and dissolve oil in water to give frothy solution the characteristic white colour of milk, followed by addition of caustic soda to neutralise acidity which  prevents it from turning sour during transportation. Urea, sugar and salt are  also added in this milk for solid and non- fat value adjustments. Then this milk is mixed in various proportions with natural milk. It appears that some milk vendors including packaging milk vendors have mastered this trick of adulteration for huge profit margins.

4.Which of the following is not a metalloid?

[A] Boron
[B] Silicon
[C] Germanium
[D] Titanium

 

Correct Answer: D [ Titanium]

Notes:
The most commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. The other less recognised metalloids are: carbon, aluminium, selenium, polonium and astatine.Titanium is a lustrous transition metal with a silver color, low density and high strength.

5.Consider the following pairs of compounds with their chemical names:

1. Blue vitriol – copper sulphate
2. White vitriol –  zinc sulphate
3. Green vitriol –  iron(II) sulphate

Which of the above is/are correct?

[A] 1 & 2 Only
[B] 3 Only
[C] 2 & 3 Only
[D] 1, 2 & 3

 

Correct Answer: D [ 1, 2 & 3]

Notes:
All given pairs are correctly matched

6.Consider the following pairs:

1. Strontium carbonate – Red fireworks
2. Barium chloride – Green fireworks
3. Copper chloride – Blue fireworks
4. Sodium nitrate – Yellow fireworks

Which of the above are correct?

[A] 1 & 2 Only
[B] 2 & 3 Only
[C] 1, 2 & 3 Only
[D] 1, 2, 3 & 4

 

Correct Answer: D [ 1, 2, 3 & 4]

Notes:
All given pairs are correctly matched
Pyrotechnic Stars are pellets or simply a composition of metal salts that are packed into a firework as pea. The concoction of metals generally consists of potassium nitrate, charcoal, and sulphur. Different metal salts are responsible for different colours. For example, strontium carbonate (red fireworks), calcium chloride (orange fireworks), sodium nitrate (yellow fireworks), barium chloride (green fireworks) and copper chloride (blue fireworks). Purple fireworks are typically produced by use of a mixture of strontium (red) and copper (blue) compounds.

7. Which of the following can be used as coolant in a nuclear reactor?

1. Carbon dioxide
2. Liquid sodium
3. Helium (He) gas

Select the correct option from codes given below:

[A] 1 & 2 Only
[B] 2 & 3 Only
[C] 1 & 3 Only
[D] 1, 2 & 3

 

Correct Answer: D [ 1, 2 & 3]

Notes:
A nuclear reactor coolant is a coolant used to remove heat from the nuclear reactor core and transfer it to electrical generators and the environment. Carbon dioxide, Helium and Liquid Sodium can be used as coolant in a nuclear reactor.

8.Which of these states of matter has the maximum density?

[A] Solids
[B] Liquids
[C] Gases
[D] None of the above

 

Correct Answer: A [Solids]

Notes:
The density is maximum in case of solids. In the case of liquids, the density is less than solids but more than gases. In gases, the density is minimum.

9.What is the ratio of change in configuration to the original configuration called as?

[A] Strain
[B] Stress
[C] Elasticity
[D] Rebound

 

Correct Answer: A [Strain]

Notes:
The ratio of change in configuration to the original configuration is called strain. Strain are of three types : 1. Linear 2. Volumetric 3. Shearing

10.Which of the following strains is produced in a body if the deforming force produces a change in the shape of the body without changing its volume?

[A] Linear
[B] Volumetric
[C] Shearing
[D] All of the above

 

Correct Answer: C [Shearing]

Notes:
If the deforming force produces a change in the shape of the body without changing its volume, the strain produced in the body is called as shearing strain. Shearing strain is defined as angle in radians through which a plane perpendicular to the fixed surface of the cubical body gets turned under the effect of tangential force.

11.What is the dimensional formula of Stress?

[A] M ¹ L^-2 T^-2
[B] M ¹ L^-1 T^-1
[C] M ¹ L¹ T^-3
[D] M ¹ L^-1 T^-2

 

Correct Answer: D [M ¹ L^-1 T^-2]

Notes:
Stress is defined as external force per unit area on a body that tends to cause it to deform. The dimensional formula of Stress is M ¹ L^-1 T^-2

12.Which of the following is NOT correct about Group 14 elements?

[A] All of them are solids
[B] Melting points are much higher than those of corresponding elements of group 13
[C] Carbon is a non-metal
[D] Germanium is a metal

 

Correct Answer: D [Germanium is a metal]

Notes:
All members of group 14 are solids. Carbon and silicon are non-metals, germanium is a metalloid, whereas tin and lead are soft metals. Melting points and boiling points of group 14 elements are much higher than those of corresponding elements of group 13.

13.Which of the following is correct about Ammonia?

[A] The ammonia molecule is trigonal pyramidal in shape
[B] Ammonia gas is light blue in colour
[C] its aqueous solution is highly basic
[D] Ammonia gas is odorless

 

Correct Answer: A [The ammonia molecule is trigonal pyramidal in shape]

Notes:
Ammonia is a colourless gas with a pungent odour. Its aqueous solution is weakly basic due to the formation of OH^– ions. The ammonia molecule is trigonal pyramidal in shape.

14.Which of the following is NOT correct about Phosphine?

[A] The chemical formula is PH₃
[B] The electronic structure is like Ammonia
[C] It is odorless
[D] it is used as a dopant in semiconductor industries

 

Correct Answer: C [It is odorless]

Notes:
Phosphine is PH₃. The electronic structure of Phosphine (pyramidal structure) is like Ammonia. It is a colourless gas and has a spoiled fish smell. It is used as a dopant in semiconductor industries.

15.Bell metal is an alloy of which of the following metals?

[A] Copper and Tin
[B] Copper and Mercury
[C] Copper and Lead
[D] Copper and Zinc

 

Correct Answer: A [Copper and Tin]

Notes:
Bell metal is a form of bronze with a higher tin content. It is an alloy of copper and tin (typically, 78% copper, 22% tin by mass). It is used for making bells and related instruments, such as cymbals.

16.Which of the following is an example of colloidal solution?

[A] Milk
[B] Fog
[C] Smoke
[D] All of the above

 

Correct Answer: D [All of the above]

Notes:
Milk, Fog, Smoke, Cheese, Clouds, Mist, Shaving cream, Butter, Jelly etc. are some of the examples of colloidal solution.

17.Which of the following statements related to principal quantum number (n) is not correct?

[A] Energy of the orbital increases with increase of n
[B] Size of an orbital increases with increase of n
[C] The shell M is represented by principal quantum number 2
[D] Total number of allowed orbitals in Shell K is 1

 

Correct Answer: C [The shell M is represented by principal quantum number 2]

Notes:
Statement 3 is incorrect. The shell M is represented by principal quantum number 3. Size of an orbital increases with increase of principal quantum number ‘n’. The energy of the orbital also increases with increase of n. Total number of allowed orbitals in Shell K is 1.

18.Which orbital will have lower energy if two orbitals have the same value of (n+l)?

[A] orbital with lower value of n
[B] orbital with lower value of l
[C] orbital with lower value of (n-l)
[D] None of the above

 

Correct Answer: A [orbital with lower value of n]

Notes:
If two orbitals have the same value of (n+l) then orbital with lower value of n will have lower energy. Also, energies of the orbitals in the same subshell decrease with increase in atomic number.

19.Which of the following is correct about Photoelectric effect?

[A] number of electrons ejected is twice the wavenumber of radiation
[B] number of electrons ejected is proportional to the intensity of light
[C] number of electrons ejected is proportional to the duration of light
[D] number of electrons ejected is not dependent on the intensity of light

 

Correct Answer: B [number of electrons ejected is proportional to the intensity of light]

Notes:
The phenomenon of ejection of electrons from the surface of metal when light of suitable frequency strikes it is called photoelectric effect. The number of electrons ejected is proportional to the intensity or brightness of light.

20.What is the S.I unit of activity?

[A] becquerel
[B] curie
[C] candela
[D] henry

 

Correct Answer: A [becquerel]

Notes:
The SI unit for activity is becquerel, named after the discoverer of radioactivity, Henry Becquerel. The c.g.s unit of activity is curie.

21.What can be the maximum number of electrons in a shell, if principal quantum number is n?

[A] n
[B] n²
[C] 2n²
[D] 3n³

 

Correct Answer: C [2n²]

Notes:
The general formula is that the nth shell can hold up to 2n² electrons. For example: for L shell n =2, so maximum number of electrons will be 2(2²) i.e. 8.

22.Which of the following sub-atomic particle accompanies an electron emission in Beta^–decay?

[A] antineutrino
[B] neutrino
[C] proton
[D] None of the above

 

Correct Answer: A [antineutrino]

Notes:
The emission of electron in β⁻decay is accompanied by the emission of an antineutrino (ν ) and in β⁺ decay, a neutrino (ν) is generated.

23.Which of the following alpha-emitter is commonly used in smoke detectors?

[A] Bismuth – 209
[B] Amrecium-231
[C] Uranium-238
[D] Protactinium-231

 

Correct Answer: B [Amrecium-231]

Notes:
Americium-241 is an isotope of americium. It is the most common isotope of americium having a half-life of 432.2 years. It is radioactive and is commonly used in ionization type smoke detectors.

24.Which is the first element in the Actinoid series?

[A] Actinium
[B] Bohrium
[C] Mendelevium
[D] Nobelium

 

Correct Answer: A [Actinium]

Notes:
The actinoid series comprises of the 15 metallic chemical elements with atomic numbers from 89 to 103 starting from actinium through lawrencium.

25.What is the shape of XeF₄ molecule?

[A] T-shaped
[B] Bent
[C] See-saw
[D] Square planar

 

Correct Answer: D [Square planar]

Notes:
The shape of XeF₄ molecule is Square planar. As per VSEPR theory, there is repulsion between lone pair electrons and bond pair electrons as a result the Xenon tetrafluoride becomes square planar to achieve the stable state.

26.Which of the following molecules have an electrovalent bonding?

[A] NaCl
[B] MgO
[C] NH₃
[D] Both a and b

 

Correct Answer: D [Both a and b]

Notes:
Both NaCl and MgO are an electrovalent compound formed by the complete transfer of electrons from one atom to another. NH₃ is a covalent compound.

27.What do we call the amount of energy required to break one mole of bonds of a particular type between two atoms in a gaseous state?

[A] Ionisation Potential
[B] Bond Enthalpy
[C] Electron affinity
[D] Bond order

 

Correct Answer: B [Bond Enthalpy]

Notes:
Bond Enthalpy is the amount of energy required to break one mole of bonds of a particular type between two atoms in a gaseous state. Its unit is KJ^-1.

28.What is the molecular geometry of a Methane molecule?

[A] Linear
[B] Trigonol Planar
[C] Tetrahedral
[D] Trigonol bipyramidal

 

Correct Answer: C [Tetrahedral]

Notes:
The hydrogen atoms sharing electrons with the central carbon atom have a 109 degree bond angle giving the molecule a tetrahedral geometry.

29.Which of the following comprises a standard hydrogen electrode?

[A] a copper electrode coated with carbon black
[B] an iron electrode coated with platinum black
[C] a platinum electrode coated with platinum black
[D] a gold electrode coated with carbon black

 

Correct Answer: C [a platinum electrode coated with platinum black]

Notes:
The standard hydrogen electrode consists of a platinum electrode coated with platinum black. According to convention, a half-cell called standard hydrogen electrode is assigned a zero potential at all temperatures corresponding to the reaction.

30.The cell constant does not depend on which of the following?

[A] distance between the electrodes
[B] area of cross-section of electrodes
[C] nature of electrolyte
[D] None of the above

 

Correct Answer: C [nature of electrolyte]

Notes:
The cell constant depends on the distance between the electrodes and their area of cross-section. It has the dimension of length^-1.

31.Which of the following types a PEM cell belongs to?

[A] Galvanic cell
[B] Fuel cell
[C] Dry cell
[D] Electrolytic cell

 

Correct Answer: B [Fuel cell]

Notes:
Proton-exchange membrane fuel cells or polymer electrolyte membrane (PEM) fuel cells (PEMFC), are a type of fuel cell which uses hydrogen gas (H2) and oxygen gas (O2) as fuel. A fuel cell is a device that converts chemical potential energy (energy stored in molecular bonds) into electrical energy.

32.Which of the following represents Reduction?

[A] Losing one or more electrons
[B] Gaining one or more electrons
[C] Losing Hydrogen atoms
[D] Liberating hydrogen gas

 

Correct Answer: B [Gaining one or more electrons]

Notes:
Reduction is a process which involves gaining one or more electrons by one of the atoms involved in the reaction. The oxidation state gets lowered after reduction.

33.What percentage of Human body is made up of carbon?

[A] 12
[B] 18.5
[C] 28.8
[D] 44.2

 

Correct Answer: B [18.5]

Notes:
Around 18.5% of Human body is made up of carbon. Carbon is the basic building block of most of the cells in the body. It helps with cellular respiration by which the human body releases energy stored in glucose.

34.Which of these is not a natural polymer?

[A] Starch
[B] cellulose
[C] Proteins
[D] Bakelite

 

Correct Answer: D [Bakelite]

Notes:
The polymers obtained from nature (plants and animals) are called natural polymers. Starch, cellulose, natural rubber, proteins, etc. are some examples. Bakelite is an example of synthetic polymer.

35.Which of the following metal is the key component of Vitamin B12?

[A] Iron
[B] Zinc
[C] Copper
[D] Cobalt

 

Correct Answer: D [Cobalt]

Notes:
Cobalt is the key component of Vitamin B12. Cobalt is a metal with atomic number 27. The cobalt metal produced by reductive smelting is hard, lustrous and silver-gray in colour.

36.Which of the following metals can easily be cut with a knife?

[A] Sodium
[B] Manganese
[C] Zinc
[D] Tin

 

Correct Answer: A [Sodium]

Notes:
Out of all the given options, Sodium is a softer metal and can be easily cut with a knife. It is a highly reactive metal which is silvery white in colour.

37.Which of the metals is most reactive out of the given options?

[A] Potassium
[B] Sodium
[C] Calcium
[D] Magnesium

 

Correct Answer: A [Potassium]

Notes:
Out of the given options, Potassium is the most reactive metal. Potassium is placed above all the given metals in the reactivity series. The reactivity series is a list of metals arranged in the order of their decreasing activities.

38.Which of the following metals is the major constituent of Pewter alloy?

[A] Tin
[B] Indium
[C] Titanium
[D] Lead

 

Correct Answer: A [Tin]

Notes:
Tin is the major constituent of Pewter alloy. It is traditionally composed of 85–99% tin, mixed with copper, antimony, bismuth.

39.Which of these metals comes into use in the treatment of bipolar disorders?

[A] Carbon
[B] Lithium
[C] Nickel
[D] Cobalt

 

Correct Answer: B [Lithium]

Notes:
Lithium salts are used as a mood-stabilizing drug in the treatment of bipolar disorder in humans. Lithium is the lightest metal and the lightest solid element.

40.Why soaps do not work in hard water?

[A] The water tastes bitter and it has an unpleasant smell
[B] The water is hard to boil and the soap only works in boiled water
[C] The insoluble soaps formed separate as scum in water
[D] The hard water has lot of impurities

 

Correct Answer: C [The insoluble soaps formed separate as scum in water]

Notes:
Hard water contains calcium and magnesium ions. These ions form insoluble calcium and magnesium soaps respectively when sodium or potassium soaps are dissolved in hard water. These insoluble soaps separate as scum in water and are useless as cleansing agent.

41.Which of these non-metals are present in Gun powder?

[A] Sulphur
[B] Carbon
[C] Nitrogen
[D] All of the above

 

Correct Answer: D [ All of the above ]

Notes:
Carbon, Nitrogen and Sulphur are the non-metals present in the Gun powder. It is a mixture of potassium nitrate, sulphur and charcoal.

42.Who among the following invented Dynamite?

[A] JB Dunlop
[B] Alfred Nobel
[C] James Simons
[D] Peter Hargreaves

 

Correct Answer: B [Alfred Nobel]

Notes:
Alfred Bernhard Nobel was a Swedish businessman, chemist, engineer, inventor, and philanthropist. Nobel held 355 different patents, dynamite being the most famous. The synthetic element nobelium was named after him.

43.What is the PH of the human blood?

[A] Highly Basic
[B] Slightly Acidic
[C] Slightly Basic
[D] Highly Acidic

 

Correct Answer: C [Slightly Basic]

Notes:
The pH scale, ranges from 0 (strongly acidic) to 14 (strongly basic or alkaline). Blood is normally slightly basic, with a normal pH range of 7.35 to 7.45. Usually the body maintains the pH of blood close to 7.40.

44.Most liquids that conduct electricity are solutions of acids, base and which of the following?

[A] Aluminium
[B] Copper
[C] Iron
[D] Salts

 

Correct Answer: D [Salts]

Notes:
Solutions that contain ions are good conductors of electricity, such as, acids, bases, salt water. Tap water, lemon juice and mercury is the best liquid conductor compare with others. Because of any solution to conduct, you need ions or free electrons.

45.Which of the following scientists is known for using electrolysis to isolate and discover many elements?

[A] Humphry Davy
[B] James Burrow
[C] John Pringle
[D] Davies Gilbert

 

Correct Answer: A [Humphry Davy]

Notes:
Sir Humphry Davy (1778 – 1829) is best known for using electrolysis to isolate and discover many elements. He is credited with isolating or discovering sodium, calcium, boron, barium, magnesium, iodine, chlorine, and potassium. He also invented a safety lamp for miners called the Davy lamp. He also named nitrous oxide as laughing gas.

46.Who discovered Benzene?

[A] John Napier
[B] John Dalton
[C] J. J. Thomson
[D] Michael Faraday

 

Correct Answer: D [Michael Faraday]

Notes:
Although Michael Faraday (1791-1867) is primarily known for his research on electromagnetism, he made significant contributions to the field of chemistry, including discovering chlorine and carbon. Faraday also discovered benzene, contributed to the development of electrolysis, and made modern chemistry labs possible by inventing an early Bunsen burner. He is generally considered one of the greatest scientists of all time.

47.1M solution of which of the following acids will have more H⁺ Ions?

[A] Hydrochloric Acid
[B] Lactic Acid
[C] Acetic Acid
[D] Tartaric Acid

 

Correct Answer: A [Hydrochloric Acid]

Notes:
Since, HCl is a strong acid, 1 (M) HCl has higher conc. of H+ ions because it ionizes completely in aqueous solution whereas rest of the three are weak acids.

48.Which of the following acids is used in the lead storage cells?

[A] Hydrochloric Acid
[B] Sulphuric Acid
[C] Nitric Acid
[D] Phosphoric Acid

 

Correct Answer: B [Sulphuric Acid]

Notes:
Dilute sulfuric acid (H2SO4) serves as the electrolyte in a lead storage battery. The electrodes of the cells in a lead storage battery consist of lead grids. The openings of the anodic grid is filled with spongy (porous) lead. The openings of the cathodic grid is filled with lead dioxide (PBO2).

49.Due to which of the following acids, Milk tastes sour when kept in the open for sometime?

[A] Lactic Acid
[B] Citric Acid
[C] Acetic Acid
[D] Carbonic Acid

 

Correct Answer: A [Lactic Acid]

Notes:
Like many other things, milk contains bacteria, Milk also naturally contains a kind of sugar known as “lactose.” The bacteria that live in milk get energy from this special sugar and use it to reproduce to make even more bacteria. When the bacteria use the lactose sugars to reproduce, they change it from “lactose sugar” into “lactic acid,” which tastes sour.

50.

Biogas is composed of Oxygen, Carbon dioxide, Nitrogen, Hydrogen, Methane and Hydrogen Sulphide compounds. Which one of the following compounds forms the majority?

[A] Carbon dioxide
[B] Carbon monoxide
[C] Hydrogen sulphide
[D] Methane

 

Correct Answer: D [Methane ]

Notes:

Biogas or Gobar gas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops. It comprises primarily methane (CH4) and carbon dioxide (CO2) and may have small amounts of hydrogen sulphide (H2S), moisture and siloxanes. The composition of biogas varies depending upon the substrate composition, as well as the conditions within the anaerobic reactor (temperature, pH, and substrate concentration). Landfill gas typically has methane concentrations around 50%. Advanced waste treatment technologies can produce biogas with 55%–75% methane, which for reactors with free liquids can be increased to 80%–90% methane using in-situ gas purification techniques. As produced, biogas contains water vapour. The fractional volume of water vapour is a function of biogas temperature; correction of measured gas volume for water vapour content and thermal expansion is easily done via simple mathematics which yields the standardized volume of dry biogas.