Question # 1

Which one of the following statements about diamond is not true?

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the coordination number of carbon atoms is 4

diamond is an isotpe of graphite

diamond has a high melting point

diamond has a rigid tetrahedral, structure

Which one of the following does not show isomerism?

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Propane

Hexane

Butane

Pentane

Vapour pressure is not affected by

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Surface area

Intermolecular forces

Temperature

Nature of liquid

Bonding in MgO is an example of

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lonic bond

Polar bond

Covalent bond

Coordination covalent bond

All the following statements are incorrect except:

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all of the gases cannot be liquefied

increase of pressure will not decrease the inter molecular distance in a gas

gas molecules do not attract each other at very low temperature

actual volume of a gas is not negligible at very pressure

UV rays inactivate enzymes because they

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change sequence of amino acids of enzymes

They add prosthetic group to them

They increase their specificity

affect structure of enzymes

During space flights, astronauts ohlained water from

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Nickel cadmium cells

Lead accumulator

Fuel Cell

Alkaline battery

Amorphous substance show

(i) Short and long range order

(ii) Short range order

(iii) Long range order

(iv) Have no sharp melting point

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(i) and (ii) are correct

(ii) and (iv) are correct

(ii) (iii) and (iv) are correct

(i) and (iv) are correct

In order to mention boiling point of water at 110∘C the external pressure should be:-

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between 760 torar an 1200 torr

between 200 torr and 760 torr

765 torr

any value of preessure

Which one of the following elements is most electropositive out of group I -A and II-A group?

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K

Mg

Na

Ca

Acetaldehyde cyanohydrin upon hydrolysis prodnces

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Tartaric acid

Malonic acid

Formic acid

Lactic acid

Oils and fats belong to the class of

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Alcohols

Hydrocarbons

Acids

Esters

Equal masses of methane and oxygen are mixed in an empty container at 25∘C.

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1/3

8/9

1/9

16/17

Molten lead and iead (II) bromide both conduct electricity. Which one of the following statements relating to this is true?

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Both undergo chemical change when they conduct

Both conduct by the movement of charge particles

Both will also conduct in the solid state

Both contain mobile electrons

When purely alcoholic solution of sodium/potassiumhydroxide and halogenoalkanes are reacted an alkene is formed, what is the mechanism of reaction?

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Elimination

Debromination

Dehydration

Reduction

By increasing the concentration of reactants, the rate of reaction

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Decreases

Increases

Remains constant

Not predicted

How many esters are possible for C2H8O2

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3

2

4

5

Which of the following statement about graphite is not true?

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The coordination number of carbon atoms is 4.

the carbon atoms are arranged layers.

the layers in graphite are attracted to each other weak forces.

the corbon atoms use only three of their four outer electrons for covalent bonding.

The pressure of 5dm³gas increase from 250 torr to 500 torr then new volume of gas

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500 cm³

375 cm³

2500 cm³

None of these

Consider gas is measure in bars then the units of rate of reaction is

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Mole dm-3 sec

Bars sec

Mole dm-3 sec-1

Bars sec-1

A student put two eggs A and B in HCL solution, After five minutes he took them out for weighing but egg dropped in water accidentally. The student was able to take it out after 30 minutes, He weighed it, Its weight was 40.33g. Weight of egg B was also 40.33g. Teacher told him that if both eggs have been dropped in water, the weight of egg B would have been:

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equal to that of egg A

less than that of egg A

greater than that of egg A

unaffected instead

Electrons in 5d energy level are filled up in case of

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Lanthanides

Transition metals

Actinides

Rare gases

In which of the following processes the liquids are made to boil at low temperature

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Vacuum distillation

Destructive distillation

Distillation

Vacuum destructive distillation

A substances has M_r74.5, a melting point of 772°C and a boiling point of 1407°C. It conducts electricity only when in the liquid state.What is the bonding present in this substances?

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covalent

ionic

metallic

hydrogen bonding

The highest oxidation state of manganese is

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+7

-7

+6

+4

The process in which solid is directly coverted into gaseous state is called

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evaporation

boiling

sublimation

transformation

The exothermic process is

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Evaporation

Sublimation

Respiration

Boiling

The boiling point of Kr is higher (-152.23°C) than that of helium (-268.6°C) due to

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Kr forms greater number of covalent bonds

greater polarizability of Kr than He

Kr has lowest freezing point

Kr is in liquid state at ordinary temperature

What will be the shape of a molecule which containstwo sigma bond pairs and one lone pair?

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Linear

V shape

Tetragonal

Triangular

Which of the following is pure substance

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Distilled water

, Sea water

, NaCl (aq)

Brass

All gases can be compressed by:

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Keeping constant pressure

Decreasing pressure

Increasing pressure

None of above

Acetone and Chloroform are soluble in each other due to

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intermolecular hydrogen bonding

ion-dipole interaction

instantaneous dipoles

dipole-induced dipole interaction

Which of the following is not a macromolecule?

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diamond

graphite

iodine

silica

The specie that develops strongest hydrogen bonding with water

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НСООН

B.CH3CH2СООН

CH3СООН

CICH2COOH

Compressibility factor for an ideal gas is

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1.5

1.0

2.0

0.5

C-H bond length in the benzene is

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0.99A°

1.09A°

1.12A°

1.34A°

Diamond is a bad conductor because

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it has light structure

it has a high density

there are no free electron present in the crystal of diamond to conduct electricity

it transparent to light

At room temperature, the vapour pressure of water and ether will be

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equal

different

zero

almost same

Diamond and silicon carbide are insoluble in all solvents because

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they have high melting and boiling points

absence of three electrons

they are huge giant three dimensional molecules (macromolecules)

their unit cells have tetrahedral geometry

The curve which is obtain from Boyle's law is called as

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Isochoric

Isotherm

Adiabatic

All of these

Which is the following would have most like an ideal gas at room temperature?

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carbon dioxide

helium

hydrogen

nitrogen

Density of a gas is usually expressed in

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Kg m³

Kg dm³

g dm^-3

g cm^-3

Which of the following test is not given by aldehvde

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2. 4 DNPH test

NaHSO3 test

Tollen's test

Sodium nitroprusside test

The pressure exerted by the vapours in equilibrium with its pure liquid at given temperature is called the

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equilibrium pressure

atmospheric pressure

vapour pressure

external pressure

Glucose and fructose are isomers

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Chain isomers

Position isomers

Functional group isomers

Metamers

Formation of Picric acid from phenol needs heating, one possible reason for it is

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acidity of phenol

e- donating nature of-OH

acidity of picric acid

e- with drawing effect of- NO2

Instantaneous dipole-induced dipole forces are also known as:

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dipole-dipole interactions

hydrogen bonds

covlent bonds

Van der Waals forces

Rte of evaporation of petrol is greater than that of water at room temperature. This is due to the reason that:

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petrol is an organic compound

water molecules have small size

petrol molecules do not have

petrol molecules have greater size

The process of effusion is best understood by law

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Grahams

Boyle s

Charles s

Avogadro s

Benzene in the presence of AICl3 produces acetophenone when reacts with

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AcetyI chloride

EthyI benzene

Acetic acid

Ethanoic acic

How many electrons have to be removed to ionize 1.0 x 10(-6) moles of Ne atoms to Ne+ ions in a neon advertising tube:

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6.02x10ê23/1.0x10ê-6

1.0x 10ê-6 x 6.02x 10ê23

1.0x10ê-6 x 6.02×10ê23/20.2

1.0x10ê-6 x 6.02x10ê23/9.65x10ê-1

What is the formula of magnesite?

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PbS

MgSO4. 7H2O

MgCO3

CaCO3

The minimum temperature recorded by Kelvin scale is:

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273K

373K

Absolute scale is unable

0K to record this temperature

Equal volume of all gases at same temperature and pressure contain number of molecules

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different

multiples

equal

in fractions

Which of the following alkyl halides undergoes SN1 reaction fastest

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Methyl chloride

Isobutyl chlorido

Ethy l chloride

Tertiary butyl chloride

Covalent bonds are least likely to be formed:

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between atoms of the same element

between atoms of different elements on the right of the periodic table

by head of the group elements with high ionization energies

between an element in Group I and an element in Group Vll

Which of the following contains maximum of number of molecules?

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100 cc of CO₂ at STP

150 cc of N₂at STP

50 cc of SO₂ at STP

200 cc of NH₃ at STP

London forces are

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stronger than dipole-dipole interactions

weaker than dipole-dipole interactions

equal to dipole-dipole interactions

sometimes stronger and sometimes weaker than dipole-dipole interactions

One of the following metals is the most reactive and form super oxide. Indicate that

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Mg

K

Be

Li

The element with highest E°red

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N

F

O

CI