JEE Main Chemistry Mock - 7 | 25 Questions MCQ Test

QUESTION: 1

Primary and secondary alcohols on action of red hot copper give

A.
Aldehydes and ketones respectively
B.
Ketones and Aldehydes respectively
C.
Only aldehydes
D.
Only ketones

Solution:

QUESTION: 2

Which of the following is hypnotic ?

A.
Acetaldehyde
B.
Metaldehyde
C.
Paraldehyde
D.
None

Solution:

Solution :

Hypnotic or soporific drugs, commonly known as sleeping pills, are a class of psychoactive drugs whose primary function is to induce sleep and to be used in the treatment of insomnia, or surgical anesthesia.

QUESTION: 3

Enzymes are made up of

A.
edible proteins
B.
proteins with specific structure
C.
nitrogen containing carbohydrates
D.
carbohydrates

Solution:

QUESTION: 4

The order of decrease in atomic radii for Be, Na and Mg is

A.
$N a > M g > B e$
B.
$M g > N a > B e$
C.
$B e > N a > M g$
D.
$B e > M g > N a$

Solution: As we move from left to right in a period, nuclear charge increases while the number of the shells remains the same. Due to this, the valence electrons are pulled little closer to the nucleus and this results in a decrease of the atomic radius. For example, when we move from Li to Be, atomic size decreases. On the other hand, the atomic radii of elements increase with increase in atomic numbers as we move from top to bottom in a group.This is due to the addition of new energy shells in each succeeding element. Thus, as we move from Li to Na, atomic radius increases and when go from Na to Mg, atomic radius decreases but not as much as in case of Be.

QUESTION: 5

Which of the following gives blood red colour with KCNS ?

A.
Cu²⁺
B.
Fe³⁺
C.
Al³⁺
D.
Zn²⁺

Solution:

[B]

Fe+3 give blood red cloour with KCNS.

[Fe(CNS)2]+

x − 2 = + 1

x = + 3

QUESTION: 6

Given that
(i) C + O₂ → CO₂ ; ∆H^o = − xkJ,
(ii) 2CO + O₂ → 2CO₂ ; ∆H^o = −ykJ .
The enthalpy of formation of carbon monoxide will be

A.
y-2x
B.
2x-y/2
C.
y-2x/2
D.
2x-y

Solution:

QUESTION: 7

The rate at which a substance reacts depends on its

A.
atomic weight
B.
atomic number
C.
molecular weight
D.
active mass

Solution:

QUESTION: 8

[Co(NH₃)₄(NO₂)₂]Cl exhibits

A.
linkage isomerism, geometrical isomerism and optical isomerism
B.
linkage isomerism, ionization isomerism and optical isomerism
C.
linkage isomerism, ionization isomerism and geometrical isomerism
D.
ionization isomerism, geometrical isomerism and optical isomerism

Solution:

QUESTION: 9

Strong electrolytes are those which

A.
Dissolve readily in water
B.
Conduct electricity
C.
Dissociate into ions at high dilution
D.
Completely dissociate into ions at all dilutions

Solution:

QUESTION: 10

Which of the following reagent can be used to convert benzene diazonium chloride into benzene ?

A.
CH₃OH
B.
H₃PO₂
C.
Br₂-H₂O
D.
LiAlH₄

Solution:

QUESTION: 11

In the electrochemical cell Pt, H₂(g) 1 atm ∕ H⁺(I M) ∕ Cu²⁺ (I M) ∕ Cu(s) . Which one of the following statements is true?

A.
H₂ is cathode, Cu is anode
B.
Oxidation Occurs at Cu electrode
C.
Reduction Occurs at H₂ electrode
D.
H₂ is anode, Cu is cathode

Solution:

QUESTION: 12

pH of the solution at 25⁰C is 2. If the pH is to be doubled then the hydronium ion concentration of the solution should be

A.
halved
B.
doubled
C.
increased to 100 times
D.
decreased to 100 times

Solution:

QUESTION: 13

The pH of 10 M HCl aqueous solution is

A.
less than 0
B.
zero
C.
2
D.
1

Solution:

QUESTION: 14

Given that K_a for acetic acid as 1.8x10⁻⁵ and K_b of NH₄OH as 1.8x10⁻⁵ at 25^oC,predict the nature of aqueous solution of ammonium acetate

A.
Acidic
B.
Basic
C.
Slightly acidic or basic
D.
Neutral

Solution:

QUESTION: 15

Highest pH (14) is shown by

A.
0.1 M H₂SO₄
B.
0.1 M NaOH
C.
1 N NaOH
D.
1 N HCl

Solution:

QUESTION: 16

Which of the following compound does not react with metallic sodium?

A.
CH₃CH(OH)CH₃
B.
CH₃―O―CH₃
C.
CH₃COOH
D.
C₂H₅OH

Solution: (B) is methyl ether, presumably water free, and unreactive under normal conditions. Of course, at room temperature, it will be a gas.

QUESTION: 17

Which of the following polymer is formed when caprolactum is heated with the traces of water?

A.
nylon-6
B.
nylon-6, 6
C.
nylon-6, 10
D.
nylon-6, 12

Solution:

QUESTION: 18

Ethane is obtained from ethylene by which of the following methods?

A.
Wurtz reaction
B.
Dehydrogenation
C.
Frakland reaction
D.
Sabatier-Senderens reduction

Solution:

QUESTION: 19

Which of the following is an example of body centred cube?

A.
Magnesium
B.
zinc
C.
Copper
D.
Sodium

Solution:

QUESTION: 20

Which of the following metal oxides is antiferromagnetic in nature?

A.
MnO₂
B.
TiO₂
C.
NO₂
D.
CrO₂

Solution: