Question # 1

Which is an intermediate in SN1 reaction

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Ethoxide ion

Carbocation

alkyl halide

alkene

The carbon atom of an alkyl group attached with halogen atom is called

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Electrophile

Free redical

Nucleophile

Nucleophilic centre

Which of the following is not a macromolecule?

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diamond

graphite

iodine

silica

When a metal rod is dipped in its one molar ionie solution

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Electricity is produced

Electricity is consumed

Redox reaction occurs

Potential difference is set up

Which of the following laws study the pressure-volume relationship of a gas at constant temperature,we get

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a straight line

a curve with different peaks

straight line parallel to x-axis

a curve called isotherm

The reduction potentials of non-metals are A =+0.54V, B=+1.08V, C=+1.36V. D= +2.87V Which non -metal can displace all other from aqucous solution of their salts

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A

C

B

D

The alkaline hydrolysis of bromoethane shown below gives alcohol as the product: H3C-CH2-Br-------H3C-CH2-OH

The reagent and the condition used in this reaction may be:

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H20 at room temperature

KOH in alcohol

Ethanol. heat

Dilute NaOH(aq) warm

In MgCl2, the oxidation state ofCI is

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Zero

-2

+2

-1

Van der Waal's forces exist in

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Polar compounds

Non-polar

Covalent

All types of atoms and molecules

Dipole-dipole forces are present between:

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non-polar molecules

polar molecules

both polar and non-polar

none pf above

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.

Succinic thiokinase is an enzyme of the type

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mutase

peroxidase

ligase

lyase

Which of the following statements about amorphous solids is incorrect?

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They melt over a range of temperature

They are anisotropic

There is no orderly arrangement of particles

They are rigid and icompressible

The units of ionic product of H2O is

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Mole dm-3

Mole2 dm-6

Mole-1 dm-3

Mole-2 dm-6

At 100 atm, CH₄ develops:

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Ideal attitude

Non-ideal attitude

Serious attitude

Laughing attitude

At higher temperature what is true for gases

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pressure is decreased

volume is decreased

number of moles are decreased

KE is increased

Amorphous solids:

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have sharp melting point

undergo clean cleavage when cut with knife

have prefect arrangement of atoms

can possesses small regions of orderly arrangement

Which of the following alcohol is more soluble in H2O

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Propanol

Butanol

Pentanol

Hexanol

If volume of an ideal gas at 0C° 536cm3, what is volume at 1°C

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373 cm3

646 cm3

Becomes 0cm3

746 cm3

Which of the following gives positive haloform test and positive Fehling solution

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Acetone

Echanol

Acetaldehyde

Formaldehyde

Molar mass of formic acid in benzene comes out to be

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64

46

32

92

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

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equal

different

zero

almost same

Oxidation state of Mn' in KMnO4. K2MnO4, MnO2 and MnSO4 is in the order

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+7.+6.+2,+4

+6,+7,+2,+4

+7. +6.+4.+2

+4, +6, +7,+2

Which of the following is a pseudo solid?

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CaF₂

glass

NaCl

all these

What is the sequence of electron take up and removal from 4s orbital a transition metal in 3d series?

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Enters first, leaves after 3d electrons removal

Enters after 3d electrons, leaves after 3d electrons

Enters after 3d eleetrons, leaves first

Enters first and leaves first

The Kw. of water at 25 C° is given by

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10(-7)

10(-10)

10(-12)

10(-14)

H2O and HF are the hydrides of the second period. Fluorine is more electronegative than oxygen. Anyhow, the boiling point of water is greater than that of HF. This is due to:

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water is more polar than HF

water has a bent structure

HF has a zig zag structure after making hydrogen bonding

the number of hydrogen bonds produced by water are greater than that of HF

The maximum hydrogen bonding is in:

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diethyl ether

ethanol

water

benzene

Change in enthalpy (∆H) of a system can be calculated by

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∆H=∆E - PV

ΔH =ΔE +q

∆H = ∆E - q

∆Η = ΔΕ + P∆V

Primany aleohols sornally give us aldehyde when oxidized in the presence of acidified Na2Cr2O7, what will be the product, when the secondary alcohols are oxidized in same condition?

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Alkenes

Alkyl halide

Alkynes

Ketones

If empirical formula of a compound is CH2 and its molecular mass is 56amu. What will beits molecular formula

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CH2

C3H6

C2H4

C4H8

Relationship between volume of a gas and prevailing conditions of temperature and pressure are called

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Gas laws

Equilibrium laws

Rate laws

None of these

The highest temperature above which a gas cannot be liquified no matter how much pressure is applied, is called as

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critical temperature

absolute zero

liquefaction temperature

boiling point

One Pascal is equal to

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1 Nm^-2

1 Nm

1 Nm^-1

1 Nm²

Saturated hydrocarbons having carbon atoms more than 20 in a molecule are solids due to

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higher densities

higher molar masses

the chain, are more zig-zag

all are correct

Glyoxal molecule has?

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two carbonyl groups

One aldehydic and one carbonyl group

Two aldehydic groups

Two carboxyl group

The gases H₂, O₂, H₂S and SO₂diffuse in the order

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SO₂>H₂S>H_2>O₂

H₂S>SO₂>O₂>H₂

O₂>SO₂>H₂>H₂S

H₂>O₂>H₂S>SO₂

Final product of hydrolysis of nitrile is

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Ketone

Alcohol

Aldehyde

Carboxylic acid

Enzymes are

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simple proteins

derived proteins

compound proteins

conjugated proteins

All are dicarboxylic acids except

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Oxalic acid

Malonic acid

Picric acid

Tartaric acid

A real gas obeying Vander Waal's equation will resemble ideal gas if

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Both a and b are large

Both a and b are small

a is small and b is large

a is large and b is small

The respiration process taking place in animals depends upon a difference in:

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vapour pressure

osmotic pressure

partial pressure

atmospheric pressure

Stability of Cu-metal is due to filled of d-orbital

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Half

Completely

Partially

Quarterly

Which one of the following metals can replace the Copper from aqueous solution of its salt more easily?

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Cd

Fe

Zn

Na

Theoretically, the temperature at which volume of gas become equal to zero is called

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Boiling point of water

Zero absolute

Zero Kelvin

both B and C

Oxygen and sulphur are present in VI-A group of the periodic table The hydride of oxygen i.e., H2O is liquid at room temperature but the hydride of sulphur (H2S) is a gas. This is due to

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greater bond angle of water than Hs

greater bond lengths in HS than H2O

hydrogen bonding in water

acidic character of HS

Beryllium differs from other elements of group Il-A due to

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high charge density

comparatively high nuclear charge

small radius

all above

Which property is associated with ionic solids?

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Solubility in polar solvents

Low melting points

Good conductivity in solid state

High vapour pressure

An element from the given below exists as discrete small molecules in the solid state. Which is that?

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Sodium

Silicon

lodine

lron

What is the formula of cryolite?

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Al2O3.2H2O

Na2B4O7 .10 H2O

Na3AIF6

Ca2B6O11. 5H2O

The forces present between the ions and water molecules are called:

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dipole-dipole forces

dipole-induced dipole forces

London dispersion forces

ion-dipole forces

How should the conditions be changed to prevent the volume of a given gas from expanding when its mass in increased

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temperature is lowered and pressure is increased

temperature is increased and pressured is lowered

temperature and pressure both are lowered

temperature and pressure both are increased

Which of the following shows group IIIB

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Zn, Cd. Hg

Cu. Ag. Au

Sc. Y. La

Ni. Pd. Pt

A temperature at which two cyrstalline forms of a substances coexist in equilibrium is called

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standard temperature

critical temperature

transition temperature

absolute temperature

The total number of lattice arrangements in different crystal system is

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7.0

3.0

8.0

14

The formation of ester from acetic aciad in presence of acid and ethanol is a

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Nucleophilic substitution reaction

Nucleophilic addition reaction

Electrophilic substituion reaction

Electrophilic addition reaction

Coordination number of Zn and ZnS (Zinc blends) is

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4

6

2

None of these

An ideal gas expands according to PV=constant. On expansion, the temperature of gas

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will rise

will drop

cannot be determined because the exteral pressure is not known

will remain same

What is the weight of 10 dm³of CO₂at 27°C and 2 atm?

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89.3 g

56.1 g

125 g

127 g

A gas is heated in such a way that its volume and absolute temperature both are doubled. the pressure of gas:

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Becomes 4 time

Becomes half

Becomes 2 time

Remains same

According to kinetic theory of gases there are

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Intermolecular attractions

Molecules which have considerable volume

No intermolecular forces of attraction

The velocity of molecules decreases for each collision.