Question # 1

The starting substance for the preparation of iodoform is any of the following, except

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СН3СН(ОН)CН3

CH3CH2ОН

HCH2OH

CH3COCH3

Inside every fluorescent lamp there is present a:

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Gas

Plasma

Liquid

Solid

Final product of hydrolysis of nitrile is

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Ketone

Alcohol

Aldehyde

Carboxylic acid

One statement of isomorphism is incorrect

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they have different chemical properties

they have same physical properties

they have same atomic ratio

they have definite geometric shape

One kilo calorie is equal to

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4.184J

1000J

4184J

1kJ

According to Boyle's law at constant temperature, the product of pressure and volume of a given mass of gas is:

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a constant

fraction

whole number

a multiple

The products of electrolysis of which of the followings are known

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Fused electrolyte

Aqueous solution of eleetrolyte

Solid electrolyte

Solid metal

The rate of E1 reaction depends upon

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The concentration of substrate

The concentration of substrate as well as nucleophile

The concentration Nucleophilic

Nature of Catalyst

The pi-electrons in the styrene are

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13

10

8

6

Which of the following pair has the same no. of electrons in d- subshell

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Sc+3,Ti+3

Mn+2,Fe+3

Ti+3,V+3

Cr+3.Co+2

The most complex strueture a single polypetide can assume is

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1° structure

2°structure

3° structure

4° structure

The surface formed by the breakage of a crystal is called _____ plane

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Crystal

Unit

Cleavage

None

Which of the following solids has a simple molecular lattice?

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magnesium oxide

sodium

silicon(IV) oxide

sulphur

The critical temperature of NH₃ is greater than CO₂ due to its:

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Greater polarity

Stable polarity

Lesser polarity

None of above

Which of the following liquid has high vapour pressure?

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H₂O

ether

CH₃OH

C₂H₅OH

Boiling point of H₂O is higher than that of HF although F is more electronegative than O. It is due to

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stronger dipole dipole forces in H₂O

H₂O is neutral HF is acidic

H₂O is angular, but HF is linear

number of hydrogen bonds more in H₂Othan in HF

Ethene can give all of the following reactions except

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Addition

Free radical substitution

Hydrohalogenation

Hydration

The reaction of formaldehyde with HCN is

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Nucleophilic substitution

Electrophilic substitution

Nucleophilic addition

Free radical addition

On ascending the electrochemical series strength as reducing agent

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Increases

Decreases

Remains same

not determinable

The value of the vapour pressure of water at its boiling point at Karachi and Murree is

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same

different

depends upon the environmental conditions in both cities

greater at Murree and less at Karachi

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

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different

multiples

equal

in fractions

The partial pressure of 0₂in the lungus is

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116 torr

159 torr

560 torr

760 torr

Hydrogen bonding is involved in

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Solubility

Detergents

Biological molecules

All the above

Which ion has maximum number of unpaired electrons in 3d subshell and shows maximum paramagnetic behavior?

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Cr+3

Ni+2

Co+2

Fe+3

An example of bydrolase is

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Amylase

Lipase

Fumarase

A,C

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

Which impurity makes the shape of NaCl crystal needle like

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MgSO4

urea

glucose

MgCO3

Gases exert pressure on walls of container because the gas molecules:

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Obey gas laws.

Have definite volume.

Collide with the walls of container.

Collide with each other.

At STP,a container has 1 mole of Ar,2 moles of CO₂,3 moles of O₂ and 4 moles of N₂.Without changing the total pressure if one mole of O₂ is removed,the partial pressure of O₂

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Is changed by about 26%

Is halved

Is unchanged

Change by 33%

The total K.E. of one mole of an ideal gas is given by:

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1/2 RT

3/2 RT

1/2 KT

3/2 KT

The radioactive disintegration of 238U92 is

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First order

Second order

Third order

Zero order

Which of the following is more reactive where 0-H bonds break

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P°alcohol

T° alcohol

S°alcohol

Cannot be predicated

All the following have crystals except:

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potassium bromide

diamond

cadmium sulphide

sodium chloride

.Both aldehydes and ketones are planar to the neighborhoods of carbonyl (C-0) group. Which one of the following bonds is distorted towards the oxygen atoms?

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pi-bond of C and O

Sigma bond of C and O

Sigma bond of C and H

Sigma bond of C and C

Ar has low critical temperature and pressure due to its

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small size

monatomic molecule

low polarizability

liquefaction temperature close to room temperature

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

The boiling point of radon (211 K) is higher than boiling point of Helium (4.4 K) because

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the atomic number of Rn is larger than that of the He

the atomic mass of Rn is larger than that of He

the dispersion forces between Rn atoms are more prominent that between He atoms

Rn atoms are joined by dipole-dipole force whereas He atoms are joined by hydrogen bonding

Surface tension is measured by

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viscometer

barometer

stalagmometer

manometer

Total heat content of a system is called

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Internal energy

Entropy

Enthalpy

All of these

Correct relationship b/w Kc and Kp can be written as

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Kp=, Kc(R)∆n

Kc=Kp (RT)∆n

Kp.= Kc.(RT)∆n

Kp=Kc (R/N)∆n

The system in which all the three axes are unequal and are at righ angle to each other is called

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cubic

hexagonal

orthorhombic

tetragonal

The element which shows highest binding energy

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V

T

So

Cr