Question # 1

If a₁, r and a_nare the first term, common ratio and the nth term respectively of a G. P. then a_n=

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a₁rⁿ

a₁r^n-1

a₁rⁿ⁺¹

a₁r

In a class of 100 students, 60 drink tea, 50 drink coffee and 30 drink both. A student from his class is selected at takes at last one of 2 drinks is

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2 / 5

3 / 5

4 / 5

None of these

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30°

45°

60°

90°

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0

3

9

-3

A and B be two square matrices and if their inverse exist the (AB)-1 =

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A-1 B-1

AB-1

A-1B

B-1A-1

The ortho center of triangle whose vertices are (0,0)(3,0)(0,4) is

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(0,0)

(1,1)

(2,2)

(3,3)

i is equal

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(1 , 0)

(0 , 1)

(1 , 1)

(0 , 0)

Number of selections of n different things out of n

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1

nPr

n!

nPr

If 2 tan¹(cos x) = tan^-1(cosec²x), then x is equal to

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π/ 3

π/ 2

π/ 6

π

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x = secθ,y = tanθ are the parametric equations of

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Circle

Hyperbola

Ellipse

parabola

The general term of a sequence is denoted by

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a₁

a_n

n

s_n

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If a^x= b^y= c^zand a, b, c are in G.P. then x, y, z are in

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A.P.

G.P.

H.P.

None of these

The distance between the points A(-8,3) and B(2,-1) is

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116

none of these

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If n is any positive integer then n! > 2^n-1for

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Multiplicative inverse of 0 is

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0

1

+-1

Does not exist

If all members of a sequence are real numbers then it is called

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A.P

Real Sequence

G.P

None of these

3x + 4 > 0 is

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equation

inequality

identity

none of these

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0

1

-1

If z=(x,y) then z has no multiplicative inverse when

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x ≠ 0, y = 0

x = 0, y = 0

x = 0, y ≠ 0

None of these

What is the axis of the parabola y²= 4ax?

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x = 0

y = 0

x = a

y = 0

Two cards are drawn at random from a well shuffled pack of cards. The probability that at least one of them is a face card is

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3 / 17

5 / 17

7 / 17

9 / 17

The central angle of an arc of a circle whose length is equal to the radius of the circle is called the

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degree

radian

minute

second

The horizontal distance between the two towers is 60 m. the angular elevation of the top of the taller tower as seen from the top of the shorter one is 30°. If the height of the taller tower is 150 m, the height of the shorter one is

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116 m

200 m

216 m

None of these

The conic is a parabola if

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e < 1

e > 1

e = 1

None of these

22.5°=______

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Two balanced dice are tossed once, the sample space when the integers on the faces of two dice are the same is

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{(1, 1), (2, 2), (3, 3)}

{(4, 4), (5, 5), (6, 6)}

{(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)}

None of these

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0

1

undefined

The distance of the point (2, -3) from x-axis is

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-2

-3

2

3

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sin (α+β) + sin (α-β)

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2 sinαcosβ

sin (2αβ)

sinαcosα

None of these

The third term in the expansion of (1+2x) is

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-2x2

-4x2

2x2

4x2

Area of inscribed circle is

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π R2

π η2

π r22

π r2

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n if n is even

0 for any natural number n

1 if in odd

None of these

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The law of sines

The law of consines

The law of tangents

None of these

Which one represents a sequence

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an

Sn

a(n)

{an}

If x-2 and x-1 both are factors of x³-3x³+2x-4p, then P must equal to

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1

2

0

-2

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The mid point of the line segment joining the points (3,-1) and (-3,1) is

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(3,-1)

(0,0)

(2,2)

(4,4)

The distance of the points (3, 4, 5) from y-axis is

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0

U

u/2

log u

If A = {x / x ∈ R ∧ x² - 16 = 0} then A =

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- x

Infinite set

Φ

{-4,4}

The roots of the equation 4x - 3.2x+2 + 32 = 0 would include

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1 and 3

1 and 4

1 and 2

2 and 3

The slope of the tangent of the circle x³ + y³ =25 at (4,3) is:

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-4/5

4/3

-25/4

25/3

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2x + 2y

4 - x²

-x/y

x/y

The function f(x) =|x| is a/an_______function

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Even

Odd

Both even as well as odd

Neither even nor odd

The sum of the odd coefficients in the expansion of (a + x)⁴is

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14

12

8

4

There are 25 tickets bearing number from 1 to 25. One ticket is drawn at random. The probability that the number on it is a multiple of 5 or 6 is

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7 / 25

9 / 25

11 / 25

None of these

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1

2

3

None of these

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π

π / 2

π / 3

π / 4

If (a, b) is the mid-point of a chord passing thro' the vertex of the parabola y²= 4x, then

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a = 2b

2a = b

a²= 2b

2a = b²

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0

1

2

3

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Evert element of A is in B

Every element of B is in A

Every element of A is in B'

Every element of A is in A

A diagonal matrix is always

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Identity

Triangular

Scalar

Non-singular

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1

-i

i

0

A subset of set of complex number whose elements are of the form (a,0) is called

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Real number

Complex number

Rational number

Irrational number

A square matrix A = [aij] is lower triangular matrix when

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aij = 0 for all i<j

bij = 0

cij = 0

dij = 0

3, 6, 12,.... is

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A.P

G.P.

H.P.

None of these

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I3

rI3

r

none

An experiment yields 3 mutually exclusive and exhaustive events A, B, C, if P(A) =2 and P(B) = 3. then P(C) =

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1 / 11

2 / 11

3 / 11

6 / 11

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trigonometric equation

conditional equation

identity

None

In the expansion of (x+y)n the coefficient of 5th and 12th terms are equal then n=

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12

n=14

17

n=15

Matrices A = [aij] 2 x 3 and B = [bij] 3 x 2 are suitable for

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BA

A2

AB

B2

The product of the four fourth roots of unity is

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0

1

-1

None of these

A square is inscribed in the circle x²+ y²- 2x + 4y + 3 =0. Its sides are parallel to the co-ordinate axes. Then one vertex of the square is

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The function whose range consists of just one element is called

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One-One Function

Identity Function

Onto Function

Constant Function

The sum of all odd numbers between 100 and 200 is

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6200

7500

6500

3750

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One-to-one and onto

One-to-one but not on to

Onto but not one-to-one

Neither one-to-one nor onto

The sum of first twenty odd integers in A.P is

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400

397

404

408

A sequence whose reciprocal is an A.P is called

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Oscillator

H.P

G.P

None of these

When we expand (a + 2b)⁵then

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a⁵+ 10a⁴b + 40a³b²+ 80a²b³+ 80ab⁴+ 32b⁵

a⁵+ a⁴b + a³b²+ a²b³+ ab⁴+ b⁵

5a⁵+ 4a⁴b + 3a³b²+ 2a²b³+ 1 ab⁴+ b⁵

None

Express the perimeter P of square as a function of its area A?

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P = 4√A

P =√A

P = 2A

P =π√A

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Rational

Irrational

Even

Odd

Sec 30° = ______

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A,. B, C are coincident

A, B, C are collinear

Both A and B

None of these

If the matrices A and B have the order 1 x 10 and 10 x 1 then order of AB is

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1 x 1

1 x 10

10 x 10

10 x 1

In a country, 55% of the male population has houses in cities while 30% have houses both in cities and in village. Find the percentage of the population that has house only in villages.

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45

30

25

50

202.04 is an example of

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Recurring decimals

Non-recurring decimals

Terminating decimals

None of above

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30°

45°

60°

75°

The set {1, -1, 1, -1}, form a group under

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Addition

Multiplication

Subtraction

None

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The first three terms in the expansion of (1 + x)^-2are ______

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1 - 2x + 3x²

1 - 2x - 3x²

1 + 2x + 3x²

-2 -2x + 3x²

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5 / 12

3 / 8

5 / 8

7 / 4

The sum of indicated terms of a sequence is called

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Arithmetic series

Series

Harmonic series

None of these

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1

-1

0

None of these

If f(x) = x²then f(2) is

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-2

2

4

-4

The symbol of irrational is

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W

N

Q

Q'

Union of the sets of rational and irrational numbers is called 6th set of

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Natural numbers

Real numbers

Whole numbers

Prime numbers

∀a,b ε R, ab = be is a

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Commutative law of multiplication

Closure law of multiplication

Associative law of multiplication

Multiplicative identity

The set of all antiderivaties of f(= ∫f(x)dx) is the

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Definite integral

Indefinite integral

Integral

Area

x = ________ is in the solution of 2x - 5 > 0

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0

2

-2

3

Two sets A and B are said to be disjoint if

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An open sentence formed by using the sign of equality "=" is called

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Equation

In equation

True sentence

False sentence

During redox reaction an oxidizing agent

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Gains electrons

Is oxidized

Loses electrons

Hydrolysed

Strong reducing agents gave

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Greater positive value of standard reduction potential

Greater negative value of standard reduction potential

Lesser positive value of standard reaction potential

None of these

The rate of reaction :

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Remain same as reaction proceeds.

May decrease or increase as reaction proceeds .

Increase as reaction proceeds.

Decreases as reaction proceeds.

Estimation of Na in sea water is an example of

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Numerical analysis

Qualitative analysis

Quantitative analysis

None of above

Ecosystem is a smaller unit of

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Hydrosphere

Lithosphere

Biosphere

Atmosphere

When elements of group I react with the elements of group VIA theory form

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Ionic bond

Covalent bond

Polar bond

None

The elements in which d or f-orbitals are incomplete are called

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Transition elements

Typical elements

Actinides

lanthanides

Wholer prepared urea from

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Ammonia

NH₄CNO

NH₃

Uric acid

Alkyl halides on treatment with Zn and HCI gives

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Alkanes

Alkenes

Alkynes

Alcohols

75% plant nutrients are present in the fertilizer:

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Urea

NH₄NO₃

NH₃

(NH₄)₂HPO₄

When alcohol reacts with concentreated H₂SO₄intermediate compound formed as

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carbonium ion

alkoxy ion

alkyl hydrogen sulphate

non of these

Alcohols are named by replacing 'e' of alkane with:

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al

ene

ol

one

When vapours of isopropyl alcohol are passed over heated copper, the major product obtained is

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Propane

Propylene

Acetaldehyde

Acetone

Coal is obtained from dead remains of

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Plants

Animals

Both a and b

None

Ultraviolet radiation from sun causes a reaction that produces

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Fluorides

Carbon monoxide

Sulphur dioxide

Ozone

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Three times

Six times

Nine times

Two times

Which of the following is the hardest metal among following

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Li

Na

Rb

K

Which of the following compounds contains a triple bond?

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Alkane

Alkene

Alkyne

Benzene

In the periodic table, the element with atomic number 16 will be placed in the group

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Fourteen

Sixteen

Thirteen

Fifteen

Identify the compound formed, when ethylene combines with water in the presence of 10% sulphuric acid and HgSO₄as catalyst

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Carbinol

Methanol

Ethanol

Glycol

Essential amino acids are those amino acids which

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Body can not synthesize

Body can synthesize

α-amino acids

β-amino acids

Charge to mass ratio of electron was discovered by:

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Millika.

Rutherford.

J.J. Thomson.

Chadwick.

The percentage of carbon in different types of iron products is in the order of

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Cast iron > wrought iron > steel

Wrought iron > steel > cast iron

Cast iron > steel > wrought iron

Cast iron = steel > wrought iron

Enzymes are catalysts which contain other than carbon and hydrogen one other element

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Oxygen

Sulphur

Phosphorus

Iodine

Partial pressure of a solution component is directly proportional to its mole fraction. This statement is known as

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Henry's law

Raoult's law

Distribution law

Ostwald's dilution law

If two lone pairs are present then bond angle of tetrahedral compound reduces to ______ degrees

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109.5°

107.5°

104.5°

None

Alkanes are least reactive towards:

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Acids and bases

Reducing agents

Oxidizing agents

All of these

Aromatic aldehydes undergo disproportionation in presence of sodium or potassium hydroxide to give corresponding alcohol and acid. The reaction is known as

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Wurtz reaction

Cannizzaro reaction

Friedel Craft reaction

Claisen reaction

Monosaccharides and oligosacchradies are generally called as

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Crystals

Sugars

Liquids

Non-sugars

Chief ore of aluminium is:

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Na₃AIF₆

Al₂O₃.2H₂O

Al₂O₃

Al₂O₃ .H₂O

d-block elements closely resemble in their physical and chemical properties. Which statement is incorrect

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They show variable valency

Their ions and compounds are coloured

They are good conductors of heat and electricity

Their compounds are diamagnetic

The stability of acromatic compounds decreases with ------- in the no. of its resonance structure

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Decrease

Increase

Remain constant

Partially decreases

Which of the following compound is known as oil of winter green?

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Phenyl benzoate

Phenyl salicylate

Phenyl acetate

Methyl salicylate

Which is in differnet phase form other metals

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Ni

Hg

Cd

Na

Proton was discovered by:

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Chadwick

J.J. Rhomson

Millikan.

Goldstein.

The simplest and the parent members of aromatic hydrocarbon is

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Benzene

Toluene

Biphenyis

Naphthalene

Tetrabromoethane on treatment with alcoholic zinc gives

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Ethylbromide

Ethane

Ethene

Ethyne

The molarity of the solution containing x grams (NH₄)₂SO₄in 500 cm³of the solution is 0.6 what is x

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39.6

45.1

40.5

42.7

Reaction of acids with alcohols is also known as

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Esterification

Saponification

Alkalization

None

In the electrolysis of fused bauxite (Al₂O₃2H₂O) with fused Cryolite (Na₃AlF₆) using carbon rods as anode. The product obtained at cathode is

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Na metal

F₂gas

Al metal

O₂gas

Which of the following is a member of -block

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Zn

Al

B

Br

What is the molarity of the solution that contains 20 grams of NaOH in 500 ml of solution [Na = 23, O = 16, H = 1]

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0.25

0.5

1

20

During electrolysis, electrons are :

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Lost by anions and gained by cations

Gained by anions and lost by cations

Gained only

Lost only

Oxidation number of oxygen in OF₂is

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+1

-1

+2

-2

Which bond is most stable

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C - Cl

C - F

C - Br

C - I

Which compound shows more hydrogen bonding?

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C₂H₆

C₂H₅Cl

CH₃----O----CH₃

C₂H₅OH

The correct set of quantum numbers (n,l and m) respectively of the unpaired electron of chlorine atom is

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2,1,0

2,1,1

3,1,1

3,2,1

Closed chain compound can be classified into

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Homocyclic

Hetrocyclic

Aliphatic

Both a and b

which of the following has smaller size:

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Fe+³

Fe+²

Fe+¹

Fe

Platinum (IV) chloride combines with ammonia to form compounds in which the coordination number of the platinum is 6. A formula unit on one of the compound contains a cation and only two chloride ions. What is the formula of this compound

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Pt(NH₃)₆CI₄

Pt(NH₃)₅CI₄

Pt(NH₃)₄CI₄

Pt(NH₃)₃CI₄

The protein which only yield amino acids and their derivatives

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Simple proteins

Complex proteins

Derived protein

All of these

The concentration units independent of temperature would be

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Normality

Mass-volume precent

Molality

Molarity

The element caesium bears resemblance with

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Ca

Cr

Rubidium

None of the above

Ascorbic acid is a chemical name of

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Vitamin D

Vitamin A

Vitamin C

Vitamin B₆

At present oil refineries in Pakistan are:

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One

Two

Three

Four

What is wrong about transition metals?

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Diamagnetic

Paramagnetic

Form complexes

Shows variable oxidation state

Amongst the following the compound that can be most readily sulphonated is

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Toluene

Benzene

Nitrobenzene

Chlorobenzene

Keeping in view the size of atoms, which order is the correct one

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Mg > Sr

Ba > Mg

Lu > Ce

Cl > l

Amino acids contain functional groups in it:

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--CO--

--OH

---NH₂

All of these

The natural fertilizers consist of

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Plants

Animals

Both plants and animals

Microorganisms

Dehydration of glycerol give

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Propane

Propene

Acrolein

Benzene

Which element should have the greatest value for electronegativity when combined with hydrogen

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Na

Si

S

Cl

50 mL of 10 N H₂SO₄. 25mL of 12 N Hcl and 40 mL of 5N HNO₃are mixed and the volume of the mixture is made 100 mL by adding water. The normality of resulting will be

Choose an answer

1 N

2 N

3 N

9 N

Given data

(i) heat of formation of CO₂is -393.7 KJ mole^-1

(ii) heat of formation of H₂O is -285.8 KH mole^-1

(iii) heat of combustion of CH_{4 is -890.00 KJ mole}^-1

Enthalpy of formation of methane from C and H₂is calculated by Hess's law by

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Adding i + ii + iii

Adding 2(i) and ii and subtracting iii

adding i + iii and subtracting ii

Adding i + 2(ii) and subtracting iii

Size of an anion is increased as compared to its atom because of the

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Addition of new shell

Repulsion of electrons in the valence shell

Decrease in nuclear charge

Increase in the unclear charge

What causes nitrogen to be chemically inert?

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Multiple bond formation in the molecule

Absence of bond distance

Short internuclear distance

High bond energy

Which is a mixture of low boiling hydrocarbon

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Natural gas

Petroleum

Wood

Graphite

The value of Plank's constant 'h' is

Choose an answer

6.625 x 10^-34

6.625 x 10^-34J sec

6.625 x 10^-34KJ

6.625 x 10^-34K Cal

Which of the following is not an electrophitic substitution reaction of benzene

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Nitration

Sulphonation

Fridel-Craft alkylation

Free radical chlorination of benzene

Choose an answer

High temperature and low pressure

Low temperature and low pressure

Low temperature and high pressure

High temperature and high pressure

Pro stand for

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Valine

Alamine

Glycine

Proline

Sodium chloride imparts a yellow colour to the Bunsen flame. This can be interpreted due to the

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low ionization energy of sodium

sublimation of metallic sodium to give yellow vapour

emission of excess energy absorbed as a radiation in the visible region as a radiation in the visible region

photosenitivity

The temp. and pressure used for PVC polymerization is

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10°C and 10 atm

20°C and 20 atm

52°C and 9 atm

100°C and 10 atm

For a 3P subshell the set of principle and azimuthal quantum number is

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n = 1 , l = 2

n = 3, l = 0

n = 3, l = 1

n = 1, l = 3

Vitamin A is present in

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Liver

Milk

Green vegetables

All

Cotton is an example of

Choose an answer

Animal fibre

Mineral fibre

Vegetable fibre

Synthetic fibre

Which of the following liquid pairs shown a positive deviation from Raoult's law

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CH₃COOH₃+ CH₃CI

C₆H₆+ CH₄OH

H₂O + HCI

H₂O + HNO₃

Electronic configuration of Cu⁺²is

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4S², 3d⁹

4s^-1, 3d¹⁰

4S⁰, 3d⁹

None of these

Which is not true about acetophenone?

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Reacts to form 2,4-dintrophenyl hydrazine

Reacts with Tollen's reagent to form silver mirror

Reacts with I₂/NaOH to form iodoform

On oxidation with alkaline KMnO₄followed by hydrolysis gives benzoic acid

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A primary alcohol

A secondary alcohol

An eher

A phenol

Benzene is obtained by fractional distillation of

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Heavy oil

Anthracene oil

Middle oil

Light oil

Which is not interstitial hydride

Choose an answer

LaH

VH

TaH

None

Gradation in properties in the periods of periodic tables are due to change in

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Atomic weight

The number of electrons

Number of protons

Electronic configuration

The major portion of natural gas is

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Ethane

Propane

Butane

Methane

The acid present in vinegar is

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CH₃COOH

HCI

H₂SO₄

HCOOH

In the modern long form of the periodic table elements are arranged in the increasing order of

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Atomic mass

Atomic number

Mass number

Isotopic number

Hydrochloric acid available in the laboratory is 36% w/w. The density of HCl solution is 1.19 g cm^-3. The molarity of HCl solution is

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10.23 moles dm^-3

11.55 moles dm^-3

11.73 moles dm^-3

12.67 moles dm^-3

On heating glycerol with conc. Sulphuric acid a compound with unpleasant odour is obtained. The compound is

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Methyl alcohol

Formic acid

Prop-2-enal

Glycerol sulphate

Eletronegativity difference in C-C bond in alkanes is:

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Zero

Double

Half

4.0

The unit of specific conductivity is

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Ohm cm^-1

Ohm cm^-2

Ohm^-1cm

Ohm^-1cm^-1

The liquid obtained after passing the mixture through filter paper is termed as:

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Extract

Residue

Filtrate

Sample

The carbon of a carbonyl group is:

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sp hybridized

sp²hybridized

sp³Hybidized

None of these

The colour of transition metal complexes is due to:

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d-d transitions of electorns

Paramagnetic nature of transition

Ionization

Loss of s-electrons

Which of the following is a characteristic of a reversible reaction?

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It never proceeds to completion

It can be influenced by a catalyst

It proceeds only in the forward direction

Number of moles of reactants and products are equal

The metal present in blood is

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Al

Hg

Cu

Fe

Those compound which have any atom other than C as member of rings are called as

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Monocyclic

Hetrocyclic

Aliphatic

Both a and b

Isotopes of an element differ in

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Number of protons

Number of electrons

Number of neutrons

Number of electrons and protons

Optical rotation method is sued when

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Reaction involve ions

Change of refractive indices

Reactions involving change of optical activity

None of the above

Which of the following compound is obtained on passing ethanol vapours on heated Al₂O₃?

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Ethylether

Acetone

Ethane

Ethanol

How much of NaOH is required to neutralize 1500 cm³of 0.1 N HCl?

Choose an answer

60 g

6 g

4 g

40 g

S_N1 reaction of alkylhalides leads to

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Retention of configuration

Recemisation

Inversion of configuration

None of these

Estimation of Na in sea water is an example of :

Choose an answer

Numerical analysis.

Qualitative analysis.

Quantitative analysis.

None of above.

Which element belong to 5d series

Choose an answer

V

Nb

Pd

Hf

In a primary alkyl halide, the halogen atom is attached to a carbon which is further attached to

Choose an answer

Only one carbon atom

Two carbon atoms

Three carbon atoms

one or no carbon atom