Chemistry Exam

Which element found in all organic compounds ?

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Carbon
Nitrogen
Calcium
None of them

The isotope atoms differ in ?

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Number of neutrons
Atomic number
Number of electrons
Atomic weight

You can't live without water! What is its chemical formula?

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H2
O2
H2O
H2O2

The metal used to recover copper from a solution of copper sulphate is ?

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Na
Ag
Hg
Fe

What is the magnitude of the restoring force exerted when an elastomer chain is extended by 25% at 25°C? Assume that the length of each bond within the elastomer backbone is 154 pm.

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0.56 pN
6.7 pN
27 pN
12 pN

What are the elements which are liquids at room temperature and standard pressure? (1) Helium (2) Mercury (3) Chlorine (4) Bromine Select the correct answer using the codes given below:

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2 and 3 only
2, 3 and 4
2 and 4 only
1 and 3 only

Consider the following statements (1) Most of the metal oxides are insoluble in water. (2) Sodium oxide and potassium oxide are metal oxides and hence insoluble in water. The correct answer is:

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Only 1 is true
Only 2 is true
1 and 2 both are true
Neither of the two is true

Why is phosphorus kept under water ?

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To make it wet
To make it durable
Water forms a protective coating on it
To save it from catching fire when exposed to dry air

Which one of the following sets of elements was primarily responsible for the origin of life on the Earth?

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Hydrogen, oxygen, sodium
Carbon, hydrogen, nitrogen
Oxygen, calcium, phosphorus
Carbon, hydrogen, potassium

Biogas majorly contains ?

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Ethane
Methane
Hydrogen
CO

Group 0 elements are ____________.

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Unreactive non metals
Reactive non metals
Reactive metals
Unreactive metals

Which of the following statements in relation to the hydrogen atom is correct?

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3s orbital is lower in energy than 3p orbital
3p orbital is lower in energy than 3d orbital
3s and 3p orbitals are of lower energy than 3d orbital
3s, 3p and 3d orbitals all have the same energy

What is “ Kiss of death” ?

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A flower whose smell was the basis of a discovery on smell that led to award of 2004 Nobel Prize in Medicine.
A chemical whose discovery ultimately won the scientists the 2004 Nobel Prize in Chemistry
A good wine flavour working on which scientist won the 2004 Nobel Prize in Chemistry
A network in brain associated with smell whose discovery led the scientists win the 2004 Nobel Prize in Physiology and Medicine

Which have the maximum density ?

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Water
Benzene
Ice
Chloroform

In Langmuir’s model of adsorption of a gas on a solid surface:

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The rate of dissociation of adsorbed molecules from the surface does not depend on the surface covered
The adsorption at a single site on the surface may involve multiple molecules at the same time
The mass of gas striking a given area of surface is proportional to the pressure of the gas
The mass of gas striking a given area of surface is independent of the pressure of the gas

The term PVC used in the plastic industry stands for:

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Polyvinyl chloride
Polyvinyl carbobate
Phosphor vanadiu chloride
Phosphavinyl chloride

The metal used to recover copper from a solution of copper sulphate is:

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Na
Ag
Hg
Fe

Acid rain is due to air pollution by ?

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Carbon dioxide
Carbon monoxide
Methane
Nitrous oxide and Sulphur dioxide

The luster of a metal is due to :

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High polishing
High density
Chemical inertness
Presence of free electrons

The ESR spectrum of the quinoxaline anion features fine structure resulting from the coupling of the electron spin to the hydrogen nuclei. The observed coupling constants are shown below. Calculate the spin densities on each of the carbon atoms at the positions labelled.

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0.156, 0.298, 0.226
0.125, 0.089, 0.051
0.016, 0.007, 0.003
0.281, 0.200, 0.115

The blue colour of water in the sea. What is the reason behind the phenomenon?

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Refraction of the blue light by the impurities in sea water
Scattering of blue light by water molecules
Refraction of blue sky by sea water
Absorption of other colours except the blue colour by water molecules

The oxide of Nitrogen used in medicine as anaesthetic is ?

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Nitrogen pentoxide
Nitrous oxide
Nitric oxide
Nitrogen dioxide

Which types of isomerism is shown by 2,3-dichlorobutane?

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Diastereo
Optical
Geometric
Structural

Nail polish remover contains ?

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Benzene
Acetic acid
Acetone
Petroleum ether

What is the chemical name of table salt ?

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Sodium nitrate
Ammonium chloride
Sodium chloride
Calcium chloride

What is the general formula of Alkanes?

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No. of hydrogen atoms is triple the no. of carbon atom plus tw
No. of hydrogen atoms is double the no. of carbon atom plus two
No. of hydrogen atoms is double the no. of carbon atom
No. of hydrogen atoms is double the no. of carbon atom plus four

The oil used in the froth floatation process is:

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Coconut oil
Olive oil
Kerosene oil
Pine oil

Which one among the following elements/ions is essential in small quantities for development of healthy teeth but causes mottling of the teeth if consumed in higher quantities?

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Fluoride
Iron
Chloride
Potassium

The electron in a hydrogen atom makes a transition from an excited state of state the ground Which of the following statements is true ?

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Its kinetic energy increases and its potential and total energy decreass
Its kinetic energy decreases, potential energy increases and its the total energy remains same
Its kinetic and total energy decreases and its potential energy increases
Its kinetic, potential and total energy decreases

Which one of the following gas is readily soluble in water at room temperature ?

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Chlorine
Nitrogen
Ammonia
Carbon dioxide

Chemistry Exam : Question 1 of 30