Question # 1

Denaturation of proteins is often characterised by

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Loss of biological activity

Aiways being irreversible

Being ereater the lower the temperature

Changes in primary structure

A certain buffer solution contains equal cone. of X- and HX. Ka for HX is 10(-8). The pH of buffer is

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3

11

8

14

Which one of the following is NOT a nucleophile

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NH2+

BF3

H2O

CH3-

Areal gas obeying Van der Waal's equation will resemble ideal gas ilf the:

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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

d-d transition cannot be shows by

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Cu+1

Sc+3

Zn+2

All

The average bond energy of C-Br is

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228 kJmol-1

250 kJmol-1

200 kJmol-1

290 kJmol-1

A compound X has all of the properties below. It is a liquid at 25°C it mixes completely with water it reaets with aqueous sodium hydroxide, What could X be?

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_{Ethanoic acid}

Ethene

Ethanol

Ethyl ethanoate

When a compressed gas is allowed to expand into a region of low pressure, it produce:

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Vapours

Cooling effect

Heating effect

None of above

An element that is not an essential par of proteins is

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O

N

H

S

At same temperature which substance has high kinetic energy:

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Liquid water

N₂gas in a container

Solid piece of iron

Solution of alcohol and water

The root mean square velocity of a gas is doubled when the temperature is

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reduced to half.

reduced to one-fourth

increased four times

inereased two times

When does average rate become equal to instantaneous rate of reaction

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At the start of reaction

time interval is zero

at the end of reactior

time interval approaches zero

Enthalpy of neutralization (∆H°n) per mole of H2SO4/ Ba(OH)2 is

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+57.4 kJmol-1

-114.8 kJmol-1

-57.4 kJmol-1

Which of following is oxidation state of oxygen in peroxides?

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-2

1/2

-1

+2

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

In which system hydrogen bonding is not present

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solution of ethanol in water

linking of helix in protein molecule

structure of ice

solution of NaCl in benzene

Propanone does not undergo

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Oxime formation

Reduction of Fehling solution

Hydrazone formation with hydrazine

Reaction with HCN

The system in which two out of three axes are of equal length and angles are all 90°

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cubic system

hexagonal system

trigonal system

tetragonal system

Neutralization of acid-base is

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Spontaneous

Exothermic

Non spontaneous

Both "a" and "c

State of hybridization of carbon in the carbocation is

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sp3

sp

sp2

dsp2

Plaster of Paris is obtained from

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marble

bauxite

gypsum

limestone

The sole produets of combustion analysis are

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CO2 and NH3

H2O and Mg(CIO4)2

CO2 and KOH

CO2 and H2O

Which order of vapour pressure in the following liquids is correct

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water > ethanol > acetone > ether

ether > acetone > ethanol > water

ether > ethanol > acetone > water

water > ether > acetone > ethanol

A graph is plotted, P on x-axis and V on y-axis for a given mass at constant temperature, we shall get:

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a curve with different peaks

a curve called isotherm

straight line parallel to x-axis

a straight line

Value of gas constant R is

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8.314 J K^-1mol^-1

0.082 J K^-1mol^-1

273.15 J K^-1mol^-1

101325 J K^-1mol^-1

A transition element X has a configuration [Ar) 4s3dd in its +3 oxidation state. Its atomic number is

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25

26

22

19

For the reaction H2(g) +I2 (g) <---------> 2Hl(g). The equilibrium constant changes with

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Total pressure

Catalyst

Concentration of H2 and I2

Temperature

The aliphatic compounds are of two types

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Straight chain and cyclic

Branched chain and alicyclic

Straight chain and branched

Homocyclic and alicyclic

The maximum possible number of hydrogen bonds in which a H₂O molecule can participate is:

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1

2

3

4

NH₃shows a maximum boiling point among the hydrides of Vth group elements due to

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very small size of nitrogen

hydrogen bonding between its molecules

enhanced electronegative character of nitrogen

pyramidal structure of NH₃

At compromise distance the forces dominating between atoms are

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repulsive forces

attractive forces

Dipole induced dipole force

H-bonding

The volume occupied by 1.4g of N2at STP is:

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2.24 dm3

1.12 dm3

112 cm3

22.4 dm3

The mass of 8.5 dm³of oxygen gas at 0.0821 atm and -1°C is

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100 g

10 g

1 g

0.1 g

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

Density of H₂gas at 0°C is 0.09 under 1 atmospheric pressure. The density of O₂gas under the same conditions of temperature and pressure is

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0.36

1.00

1.44

1.18

The best concentration unit used for K⁺ ions present in potable water is

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ppm

Mole fraction

Molarity

Molality

For reaction of methane and chlorine light is not available then

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Reaction will take place rapidly

No Reaction take place

Reaction occurs at double the rate

May all cases occur

Density of a gas is usually expressed in

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Kg m³

Kg dm³

g dm^-3

g cm^-3

Which compound is not formed as a result of reaction between acetic acid & HI & red phosphorous

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Ethanol

Water

lodine

Ethane

lonic solids don't conduct the electrical current because

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ion do not have translatory motion

free electrons are less

the coordination number of the ion is very high

strong covalent bonds are present in their structure

The maximum possible number of hydrogen bonds in which a H₂O molecule can participate is

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1

2

3

4

Enthalpy of neutralization of strong acids and strong bases have same values because

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Neutralization leads to the formation of salt and water

Acids always give rise to H+ and bases always furnish OH-

Strong acids and bases are ionic substances

The net change involves the combination of H and OH ions to form water