Chemistry Test 75

Result

Chemistry Test 75

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
4 / -1

One mole of N₂O₄(g) at 300K is kept in a closed vessel at 1atm pressure. It is heated to 600 K when 20% by mass of N₂O₄(g) decomposes to NO₂(g). The resultant pressure is

A
1.2 atm

B
2.4 atm

C
2.0 atm

D
1.0 atm

Solution
Question 2
4 / -1

HBr and HI can reduce sulphuric acid. HCl can reduce KMnO₄ and HF can reduce

A
H₂SO₄

B
KMnO₄

C
K₂Cr2O₇

D
None of the above

Solution

HF is the weakest reducing agent due to its dissociation energy. so, it cannot reduce any of the given substance.

Hence, the correct option is (D).
Question 3
4 / -1

One mole of a symmetrical alkene on ozonolysis gives two moles of a ketone having a molecular mass of 44 u. The alkene is

A
Ethene

B
But-2-ene

C
2,3 - dimethylbut - 2 - ene

D
Pent - 2 - ene

Solution
Question 4
4 / -1

Osmotic pressure is 0.0821 atm at a temperature of 300 K. Find concentration in mole/liter.

A
0.34 × 10 ^-2

B
0.33 × 10 ^-2

C
0.33 × 10 ^-4

D
0.33

Solution
Question 5
4 / -1

An organic compound containing 60.84% C, 4.35% H and the rest O gives effervescence with NaHCO₃. It also gives deep violet colouration with FeCl₃solution. The compound can be obtained from phenol by the action of CCl₄/KOH.

The formula of the compound is

A

B

C

D
None of these

Solution

Carbon tetrachloride on heating with ethanolic KOH gets hydrolyzed to form potassium chloride and potassium carbonate.

Hence, the correct option is (A).
Question 6
4 / -1

The product of the following reaction is

A
1-phenylethanol

B
2-phenylethanol

C
3-phenylethanal

D
1-phenylethanone

Solution

1-phenylethanone

Hence, the correct option is (D).
Question 7
4 / -1

When 32.25 g of ethyl chloride (atomic mass of chlorine is 35.5 g) is subjected to dehydrohalogenation reaction, the yield of the alkene formed is 50%. The mass of the ethene formed is:

A
7 g

B
28 g

C
64.5 g

D
56 g

Solution

Molar mass of ethyl chloride

=2×12+5×1+1×35.5

=24+9+35.5=64.5 gmol⁻¹

Molar mass of ethene =2+12+4×1

=28 gmol⁻¹

Actual yield = 50% of 28 g = 14 g

64.5 g of ethyl chloride on dehydrohalogenation gives 14 g ethene

32.25 g of ethyl chloride on dehydrohalogenation will give ethene = 7 g

Hence, the correct option is (A).
Question 8
4 / -1

When two ice cubes are pressed over each other, they unite to form one cube. Which of the following forces is responsible to hold them together?

A
Hydrogen bond formation

B
Van der Waals forces

C
Covalent attraction

D
Ionic interaction

Solution

When two ice cubes are pressed over each other, they unite to form one cube, Hydrogen bonding is responsible for it.

A hydrogen bond is an intermolecular force (IMF) that forms a special type of dipole-dipole attraction when a hydrogen atom bonded to a strongly electronegative atom exists in the vicinity of another electronegative atom with a lone pair of electrons. Intermolecular forces (IMFs) occur between molecules. Other examples include ordinary dipole-dipole interactions and dispersion forces. Hydrogen bonds are generally stronger than ordinary dipole-dipole and dispersion forces, but weaker than true covalent and ionic bonds.

Hence, the correct option is (A).
Question 9
4 / -1

The formation of cyanohydrin from a ketone is an example of

A
Electrophilic addition

B
Nucleophilic addition

C
Nucleophilic substitution

D
Electrophilic substitution

Solution

The formation of cyanohydrin from a ketone is an example of a nucleophilic addition reaction.

Hence, the correct option is (B).
Question 10
4 / -1

Which of the following statements is incorrect?

A
Boron halides are all monomeric, while those of Al are dimeric.

B
Boron halides and aluminium halides exist as monomeric halides.

C
Boron halides and aluminium halides are Lewis acids.

D
Boron nitride is called inorganic graphite.

Solution

The bond length and atomic size of boron in BCl₃ are smaller than in AlCl₃so, this leads to interatomic repulsion so, BCl₃ could not accept another BCl₃ via a dative bond because it leads to more repulsion and finally breaking of the dimer.

Hence, the correct option is (B).