Question # 1

Helium atom is two times heavier than a hydrogen molecule. At 298 K, the average kinetic energy of a helium atom is

Choose an answer

same as that of a hydrogen molecule

half that of a hydrogen molecule

two times that of a hydrogen molecule

four times that of hydrogen molecule

The exothermic process is

Choose an answer

Evaporation

Sublimation

Respiration

Boiling

Image a man is sitting in a room. The room is closed from all sides, no entry no exit of any gas. If the room expands suddenly then:

Choose an answer

he will be frightened

he will feel cool

his blood pressure will decrease

he will feel warmth

Keeping the temperature constant, if the gas is expended:

Choose an answer

Kinetic energy of molecules will increase.

Number of gas molecules increases.

Temperature will increase.

Pressure will decrease.

The no. of Ip's on oxygen in CO are

Choose an answer

1

3

4

2

At constant volume, for a fixed number of moles of a gas the pressure of the gas increases with size of temperature due to

Choose an answer

increase in average molecular speed

increase in number of moles

increase in molecular attraction

decrease in the distance between the molecules

A doubly bonded carbon is

Choose an answer

cannot be sp2 hybridized

can be sp hybridized

can attach with three carbons

can attach with three hydrogens

Choose the gas law which gives relationship between volume and pressure:

Choose an answer

Bolye,s law

Graham,s law

Dalton,s law

Charles,s law

For gases obeying Boyle's law, if pressure is quadrupled, the volume becomes

Choose an answer

Double

One half

One fourth

Remains constant

Butane molecule can have maximum no of isomers

Choose an answer

2

5

4

3

The value of ∆V being very small. The term P∆V can be neglected for process involving

Choose an answer

Liquid and gas

Solids and gases

Liquid and solid

None of these

Which one of the following statements is wrong for gases?

Choose an answer

gases do not have a definite shape and volume

volume of the gas is equal to volume of container confining the gas

confirmed gas exerts uniform pressure on the walls of its container in which it is enclosed

mass of gas cannot be determined by weighing a container in which it is enclosed

Alkyl halides are considered to be very reactive compounds towards nucleophiles, because

Choose an answer

The have an electrophilic carbon

They have an electrophilic carbon and a bad leaving group

They have an electrophilic carbon and a good laving group

They have a nucleophilic carbon and a good leaving group

In voltaic cell a saht bridge is used in order to

Choose an answer

Pass the electric current

Prevent the flow of ions

Mix solutions of two half cells

Allow movement of' ions between two cells

According to the kinetic theory of gases,in an ideal gas,between two successive collisions a gas molecule travels

Choose an answer

Ina circular path

In a wavy path

In a straight line path

With an accelerated velocity

Dehydrogenase is an erample of

Choose an answer

Transferase

Hydrolase

Lyase

Oxido-reductase

Methyl cyanide, on boiling with mineral acids yield

Choose an answer

Acetic acid

Formic acid

Propanoie acid

Butanoic acid

Which property of liquid is measured by polarimeter

Choose an answer

Conductance

Optical activity

Refractiye Indéx

Change in volume

Among the following molecules, which one has coordinate covalent (dative) bond?

Choose an answer

CCI4

CO2

CO

CH4

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

Choose an answer

∆H=∆E - PV

ΔH =ΔE +q

∆H = ∆E - q

∆Η = ΔΕ + P∆V

When the temperature is raised, the viscosity of the liquid decreases.This is because of

Choose an answer

Decreased volume of the solution

Increase in temperature increases the average kinetic energy of molecules which overcome the attractive force between them

Decreased covalent and hydrogen bond forces

Increased attraction between the moelcules

At higher temperature isotherm moves away from y-axis because of increase in

Choose an answer

Pressure

Number of moles

Volume

Mass

When calcium formate and calcium acetate are dry heated they form

Choose an answer

НCOOH

C2H5OH

CH3CHO

HCHO

5604 cm3 of H2 gas at STP contains atoms of hydrogen

Choose an answer

6.02×10 (23)

2.6x10(22)

3.01x10(23)

1. 50x 10(23)

Name the compound, which shows geometric isomerism

Choose an answer

I-bromo-2-chloropropene

2.3-dimethy lpropene

2-pentene

Both A & B

The height of the peak in the mass spectrum shows

Choose an answer

Number of isotopes

Relative abundance

Mass number

Number of protons

In solid, the temperature is the measure of:

Choose an answer

Rotational kinetic energies.

Translational kinetic energies.

Vibrational kinetic energies.

None of above.

Which of the following undergoes easy dehydration?

Choose an answer

3-MethyIbutan-2-ol

Ethanol

2.Methylpropan-2-ol

Methanol

When vapour pressure is equal to atmospheric pressure than it is called

Choose an answer

Evaporation

M.P

B.P

Freezing point

All of the following substances are crystalline except:

Choose an answer

carbon

ice

plastic

sucrose

According to Boyles law, at constant temperature the product of pressure and volume of a given mass of gas is

Choose an answer

whole number

a constant

fraction

a multiple

Absolute temperature is the temperature at which

Choose an answer

All molecular motion ceases

volume becomes zero

Mass becomes zero

None of these

Dehydrogenase is an example of

Choose an answer

ligase

oxidoreductase

lyase

hydrolase

Which of the elements has seven electrons in d-subshell?

Choose an answer

Zn

Co

Cu

Fe

What is the formula of cryolite?

Choose an answer

Al2O3.2H2O

Na2B4O7 .10 H2O

Na3AIF6

Ca2B6O11. 5H2O

The density of a gas is 1.964 g dm-³ at 273K and 76 cm Hg The gas is

Choose an answer

CH₄

CO₂

C₂H₄

Xe

Which of the following statement is correct if the intermolecular forces in liquids A,B and C are in the order A < B < C?

Choose an answer

B evaporates more readily than A

B evaporates less readily than C

A and B evaporates at the same rate

A evaporates more readily than C

Which of the following is a pseudo solid?

Choose an answer

CaF₂

glass

NaCl

all these

The boiling point of glycerin at 1 atmospheric pressure is:

Choose an answer

290°C

390°C

190C°

210°C

Which element is expected to show the greatest tendency to form some covalent compounds?

Choose an answer

aluminium

calcium

magnesium

sodium

Mostly ionic compounds are produced between elements of group

Choose an answer

IA and IIA

IB and VIB

IA. IIA and VII-A

IA and IB

To which of the following mixtures Dalton's law of partial pressures is not applicable?

Choose an answer

CO and CO₂

CO₂ and N₂

CH₄ and C₂H₆

HCI and NH₃

If internal energy of the system is increased

Choose an answer

Change in state of the system may occur

Temperature of the system may rise

Chemical reaction may take place

All of these

pH of an aqueous solution is 3.0 at 25°C. The hydrogen ion concentration in the solution would be

Choose an answer

0.001

0.01

0.0001

10(-5)

Glycerin boil at 290°C under normal atmospheric pressure. If the pressure is reduced to 50 mm of Hg, it will boil

Choose an answer

above the given temperature

below the given temperature

at the same temperature

at 25°C

Glycerine is a polar compound. It boils at 290°C under one atmospheric pressure. It should be distilled under reduced pressure due to reason that

Choose an answer

there are strong intermolecular forces between molecules of glycerine

it decomposes at 290°C

low pressure makes the liquid to boil at high temperature

the reduced pressure decreases the boiing point of liquids

What is the numerical value of 'R; (the gas constant) in S.I units?

Choose an answer

83143 J/mole/K

Avogadro's law

83.143 J/mole/K

8.3143 J/mole/K

In which system hydrogen bonding is not present

Choose an answer

solution of ethanol in water

linking of helix in protein molecule

structure of ice

solution of NaCl in benzene

When the concentration of product is increased the instantaneous rate of reaction with reference to reactants will be

Choose an answer

Positive

Negative

the same

falling curve

Out of monochloro, monobromo and mongiodo derivatives of ethane, the mos reactive compound towards nucleophilic substitution will be

Choose an answer

C2H5Br

C2H5Cl

C2H5I

All are equally reactive

suppose that an ocean of mercury replaced all the air of the air of the earth . How deep would this ocean have to be to exert the same pressure as the air:

Choose an answer

77cm

76cm

79cm

78cm

Acetone and chloroform are soluble in each other due to:

Choose an answer

intermolecular hydrogen bonding

dipole-dipole interaction

instantaneous dipoles

all of the above

Which of the following bonds is not present in NH4CL

Choose an answer

lonic bond

Covalent bond

Co-ordinate covalent bond

De-localized covalent bond

Styrene has empirical formula CH, and there is 92.2%C and 7.75% hydrogen. If molar mass is 104g mol¯, what will be integral multiple (n) to get molecular formula:

Choose an answer

2

4

6

8

The rate of diffusion of a gas of molar mass 72 as compared to H₂will be:

Choose an answer

Same

6 times

1.4 times

1/6 times

Which of the compounds cannot show positional isomerism?

Choose an answer

Alkanes

Alkenes

Alkynes

Alcohols

What forces operate between ethyl group of ethyl alcohol and oxygen of water

Choose an answer

H-bonding

attractive forces

repulsive forces

dipole forces

Crystals can be classified into

Choose an answer

7 crystal systems

4 crystal systems

3 crystal systems

14 crystal systems

In a group, the atomic radii from top to bottom

Choose an answer

increase

decrease

don't change

show variable trend

If ionic product is equal to Ksp then the solution is

Choose an answer

Unsaturatec

Ideal

Supersaturated

Saturated

An example of simple protein is

Choose an answer

lipoprotein

Cholesterol

lecithin

globulin