THE P-BLOCK ELEMENTS-11th Quiz-18

CHEMISTRY THE P-BLOCK ELEMENTS-11th
QUIZ-18

Dear Readers,

IIT JEE exam which consists of JEE Main and JEE Advanced is one of the most important entrance exams for engineering aspirants. The exam is held for candidates who are aspiring to pursue a career in the field of engineering and technical studies.
Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything..

Q1.Diborane is a Lewis acid forming addition compound B₂H₆.2NH₃ with NH₃, a Lewis base. This

• Is ionic and exists as [BH₂(NH₃)₂]⁺ and [BH₄]^- ions
• On heating is converted into borazine, B₃N₃H₆ (called inorganic benzene)
• Both (a) and (b) are correct
• None of the above is correct

Solution
Both (a) and (b) are correct

Q2.When a mixture of carbon monoxide and chlorine is exposed to sunlight the product formed is

•  Thionyl chloride
•  Phosgene
•  Phosphine
•  Carbon tetrachloride

Solution
CO + Cl₂ → COCl₂
                   phosgene

Q3.Nitric oxide is paramagnetic in

•  Gaseous state
•  Liquid state
•  Solid state
•  Polymeric state

Solution
Gaseous state.
Nitric oxide is gas at temperature above 123K. 7 electron of nitrogen and 6 of oxygen, 6 paired and one unpaired electron are present.
Nitric oxide (NO) have one unpaired electron in gaseous state so it is paramgnetic in gaseous state.

Q4.Nitrosonium ion (NO⁺) is isoelectronic with

•  Carbon dioxide
•  Carbon monoxide
•  Nitrogen dioxide
•  Nitric oxide

Solution
Carbon monoxide
Nitrosonium ion (NO⁺) has 14 electrons and so, it is isoelectronic with CO, which also has 14 electrons.
Nitric oxide (NO), carbon dioxide (CO₂) and nitrogen dioxide (NO₂) have 15, 22 and 23 electrons respectively.

Q5.Select the incorrect statement

•  Mellitic acid is benzene hexa-carboxylic acid
•  Pb dissolves in conc. HCl forming PbCl₂
•  Pb dissolves in hot NaOH forming Na₂[Pb(OH)₆]
•  Diamond is unreactive but graphite forms (CF)_n with F₂

Solution
H₂PbCl₆ is formed

Q6.Concentrated nitric acid, upon long standing turns yellow-brown due to the formation of

•  NO
•  NO₂
• N₂O
•  N₂O₄

Solution
4HNO₃ → 2H₂O+ 2NO₂ + 3O₂

Q7.The sides of safety matches contain

•  Red phosphorus + sand powder
•  P₄S₃
•  Ca₃PO₄ + glass pieces
•  KClO₃, KNO₃, sulphur + antimony

Solution
Red phosphorus + sand powder
The sides of safety matches contains red phosphorus + sand powder. While the head of match stick contain P₄S₃

Q8.Alum is found to contain hydrated monovalent cation [M(H₂O)₆]⁺, trivalent cation [M'(H₂O)₆]³⁺ and SO₄^2- in the ratio of

•  1:1:1
•  1:2:3
•  1:3:2
•  1:1:2

Solution
1:1:2
The formula of alum is K₂SO₄.Al₂(SO₄₃.24H₂O.
There are 2 monovalent cation, 2 trivalent cations and 4SO₄ ​⁻² ion.
Thus the ratio of hydrated monovalent cation, trivalent ion and SO₄⁻² ion is 1:1:2.

Q9.NaNO₂ and NaNO₃ are used as food additives and generally added to meat to

•  Retard oxidation of meat to brown coloured material
•  Prevent growth of botulism bacteria
•  Impart red colour to oxidized meat by NO by reaction of heme in blood
•  Make all of the functions given above effective

Solution
Make all of the functions given above effective

Q10. Select the correct statements

•  Catenation is maximum is carbon
•  Carbon has pronounced ability to form pπ-pπ multiple bonds to itself and to other elements like O and N
•  Both (a) and (b) are correct
• None of the above is correct

Solution
C=C, C=O, C≡N