Saturday, September 22, 2018

Questions With Solutions Chemistry Elements of p-Block: Groups 13,14,15,16,17 and 18

11.Which one the following statement regarding helium is incorrect ?   (2004)
(1) It is used to fill gas balloons instead of H2because it is lighter and non-inflammable
(2)It is used in gas-cooled nuclear reactors
(3)It is used to produce and sustain powerful superconducting reagents (4)It is used as cryogenic agent for carrying out experiments at low temperatures
Ans.
(1) Hydrogen is lightest and is non inflamable.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-12
Ans.(4) Hydrated and coordinated aluminium cation is farmed
13.The soldiers of Napolean army while at Alps during freezing winter suffered a serious problem as regards to the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transforma­tion is related to(2004)
(1)an interaction with nitrogen of the air at very low temperatures
(2)an interaction with water vapour contained in the humid air
(3)a change in the partial pressure of oxygen in the air
(4)a change in the crystalline structure of tin
Ans.(4) Transformation of crystal structure.
14.The number of hydrogen atom(s) attached to phosphorus atom in hypophosphorous acid is
(2005)
(1)zero 2) two 3) one 4) three
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-14
15.The correct order of the thermal stability ofhydrogen halides (H – X) is                  (2005)
(1)HI > HBr > HC1 > HF
(2)HF > HC1 > HBr > HI
(3)HC1 < HF > HBr < HI
(4)HI > HC1 < HF < HBr
Ans.(2) HF is most stable.
16.Heating an aqueous solution of aluminiumchloride to dryness will give                (2005)
(1)A1C13 2) A12C16
3) A1203    4) Al(OH)CI2
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-16
17.In silicon dioxide (2005)
(1)Each silicon atom is surrounded by four oxygen atoms and each oxygen atom is bonded to two silicon atoms
(2)Each silicon atom is surrounded by two oxygen atoms and each oxygen atom is bonded to two silicon atoms
(3)Silicon atoms is bonded to two oxygen atoms
(4)There are double bonds between silicon and oxygen atoms
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-17
18.The structure of diborane (B2Hfi) contains(2005)
(1)four 2c-2e bonds and two 3c-2e bonds
(2)two 2c-2e bonds and four 3c-2e bonds
(3)two 2c-2e bonds and two 3c-3e bonds
(4)four 2c-2e bonds and four 3c-2e bonds
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-18

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