Chemistry · NDA previous year questions

Which one among the following elements is known to be discovered the earliest?

1. A.Copper
2. B.Gold
3. C.Oxygen
4. D.Uranium

Which one of the following is a non-conventional source of energy?

1. A.Petroleum
2. B.Natural Gas
3. C.Tidal energy
4. D.Coal

Which one among the following elements is polyatomic ?

1. A.Sodium
2. B.Sulphur
3. C.Chlorine
4. D.Aluminium

Which of the following anions has a valency of -3 ?

1. A.Nitride
2. B.Nitrate
3. C.Sulphide
4. D.Sulphate

The mass of 0.5 mole of ${\mathrm{N}}_2$ gas is

1. A.$7\mathrm{g}$
2. B.$14\mathrm{g}$
3. C.$21\mathrm{g}$
4. D.$28\mathrm{g}$

The chemical reaction : $2AgCl(\mathrm{s})\to 2Ag(\mathrm{s})+\mathrm{C}{\mathrm{l}}_2(\mathrm{g})$ takes place

1. A.in dark
2. B.in sunlight
3. C.on heating
4. D.under high pressure

An astronaut whose weight on the Earth is 600 N experiences weightless- ness on International Space Station orbiting around the Earth. It means that

1. A.acceleration of the astronaut is zero
2. B.normal reaction of the space- station floor on the astronaut is zero
3. C.gravitational pull of earth on the astronaut is zero
4. D.space station applies a centrifugal force on the astronaut 2 w

Lightning is due to

1. A.The flow of charges between different parts of the cloud
2. B.The short-circuiting of charges between the upper and lower surfaces of the cloud
3. C.The collection of positively charged particles on the base and collection of negatively charged particles at the top of the cloud
4. D.The induction of positive charge on the ground below the negative charge at the base of the cloud

Which one among the following processes is NOT part of chemical weathering?

1. A.Solution
2. B.Hydration
3. C.Reduction
4. D.Thawing

What is the maximum number of electrons that can occupy the first shell of an atom?

1. A.2
2. B.4
3. C.8
4. D.16

Which one among the following has valency of 3?

1. A.Carbon
2. B.Oxygen
3. C.Nitrogen
4. D.Sodium

Which one among the following is an example of oxidation reaction?

1. A.Freezing of water
2. B.Dissolving sugar in water
3. C.Rusting of iron
4. D.Boiling of petrol

For Aluminium (Al) (atomic number: 13, mass number: 27), which one among the following statements is NOT correct?

1. A.Number of electrons present in Al is 13
2. B.Number of protons present in Al is 13
3. C.Number of neutrons present in Al is 14
4. D.The valency of Al is 2

The elemental composition of diamond is

1. A.Carbon and Hydrogen
2. B.Carbon and Oxygen
3. C.Pure Carbon
4. D.Pure Silicon

Which one among the following is an example of chemical change?

1. A.Sublimation of camphor
2. B.Melting of ice
3. C.Heating of an iron rod
4. D.Mixing of NaOH and HCI

Given below are the four cases in which certain heat transfer is taking place: 1. Ice is melting in a glass full of water 2. Water is boiling in an open container 3. A metal rod is heated in a furnace 4. A cup of coffee is allowed to cool on a table In which of the above cases, the Newton's Law of Cooling is applicable ?

1. A.1 only
2. B.4 only
3. C.1 and 4 only
4. D.1, 2 and 3

Which one of the following is the best shape of a solid metal rod to form the top end of a lightning conductor?

1. A.Option A
2. B.Option B
3. C.Option C
4. D.Option D

The relative atomic mass of boron (which exists in two isotopic forms ${}^{10}\mathrm{B}$ and ${}^{11}\mathrm{B}$) is 10.81. What will be the abundance of ${}^{10}\mathrm{B}$ and ${}^{11}\mathrm{B}$, respectively (consider a sample of 100 atoms)?

1. A.19% and 81%
2. B.81% and 19%
3. C.38% and 62%
4. D.62% and 38%

Match List-I with List-II and select the correct answer using the code given below the Lists: $$\begin{array}{ll}\text{List-I}& \text{List-II}\\ \text{(Allotrope of Carbon)}& \text{(Property)}\\ \text{A. Graphite}& \text{1. Thinnest and strongest material}\\ \text{B. Diamond}& \text{2. Hardest natural substance}\\ \text{C. Fullerene}& \text{3. Very light and strong material}\\ \text{D. Graphene}& \text{4. Soft and slippery material}\end{array}$$

1. A.A - 4, B - 2, C - 3, D - 1
2. B.A - 4, B - 3, C - 2, D - 1
3. C.A - 1, B - 3, C - 2, D - 4
4. D.A - 1, B - 2, C - 3, D - 4

Which of the following is not a part of compound microscope?

1. A.Mirror
2. B.Stage
3. C.Clip
4. D.Retina

In the human digestive system, which one among the following is the role of the pancreas?

1. A.Secretion of surfactants to break up lipid droplets
2. B.Storage and regulated release of bile
3. C.Secretion of lipase, amylase and protease
4. D.Neutralizing stomach acids

Which one of the following does not apply to sound waves in fluids?

1. A.They transport energy
2. B.They need a medium to travel
3. C.They are transverse
4. D.They travel faster in liquids than in gases

A metallic bob X of mass m is released from position A. It collides elastically with another identical bob Y placed at rest at position B on a horizontal frictionless table. The angle AOB is 30°. How high does the bob X rise immediately after the collision?

1. A.To the same height as that of position A on the other side in the same trajectory
2. B.To half the height as that of position A on the other side along the same trajectory
3. C.The same height at position A
4. D.It stops at position B

Consider the two statements given below: Statement-1 : Infrared waves are also called heat waves. Statement-2 : Water molecules readily absorb infrared waves. Select the correct answer using the code given below :

1. A.Both the statements are individually true and Statement-2 is the correct explanation of Statement-1.
2. B.Both the statements are individually true, but Statement-2 is not the correct explanation of Statement-1.
3. C.Statement-1 is true, but Statement-2 is false.
4. D.Statement-2 is true, but Statement-1 is false.

Water gas is a mixture of:

1. A.CO₂ and H₂
2. B.CO and H₂
3. C.CO₂ and H₂O
4. D.CO and H₂O