P block

Question 1

ionisation enthaply order of N family

Answer 1

I) N > P> as > Sb > Bi
ii) N > P > As> Bi > Sb
iii) N> P > As> BI > SB

Question 2

electronegativitity trnd of N

Answer 2

N> P > As> Sb = Bi

Question 3

covalent and ionic radius of N

Answer 3

COvalent
= BI>Sb > AS> P > N
Ionic
As> P > N > BI> Sb

Question 3

density of N group

Answer 3

HIgest = BI
Lowest N
Sb> As P

Question 4

why is ioni enthalpy more for grp 15 than 14 in period because

Answer 4

of smaller size and stable half filled p orbital e configuration.

Question 5

boiling point of N

Answer 5

Sb has more than Bi

Question 6

melting point

Answer 6

increases upto arsenic and then decreases upto bismuth

Question 7

which N group element forms metallic bond in elemental state

Answer 7

Bismuth

Question 8

why catenation is weak in NN
than PP

Answer 8

as high interelectronic repoulsion of non bonding electrons
small bond lenght in N

Question 9

Which bonds does NItrogen form

Answer 9

Ppi - P pi multiple bond with itself and other elecment having small size and high eng. but not heavier elements as their atomic orbitals are large, they cant have effective overlapping .

But NN cannot form DPi - P pi bonds

Question 10

the only well characterised 5 oxidation stabte compnd with BI is

Answer 10

BiF5

Question 11

trends of group 15 hydrides
BDenthalpy

Answer 11

NH3 , ph3 , ash3, sbh3, bih3
decreases
basicity - decreases
reducing character - increase
bond angle - decrease
booiling point
= PH3< Ash3< NH3< Sbh3< BIh3

Question 11

disporportionation of N in acid solution

Answer 11

all 1 - 4 dispropo.
3HNO2= Hno3 + H20 + 2NO

Question 12

trends of group 15 hydrides
thermal stability

Answer 12

NH3 , ph3 , ash3, sbh3, bih3
thermal stability decreases

Question 13

what nitrogen halide is only stable

Answer 13

NF3

Question 13

what is the only trihalide which is ionic

Answer 13

BIf3
pentahalides are more covalent than trihalides .

Question 14

during commerial liquifaction , and frac distil, of air, which gas as liquid , distils first leaving behind which other gas

Answer 14

Ns, leaves o2

Question 14

When Nh4cl reacts with X it releases gas Y , water and Nacl
what are small inpurities in this reaction , and how are they removed

Answer 14

X = Nano2
Y = N2
small amts of
NO and Hno3
removed by passing the gas through Aq h2so4 containing K2cr207

Question 14

NH4cl reacts with X to give an important gas, a moisture absorber and water

NH4)2So4 reacts with Y to give the same gas, water and Z salt

Answer 14

X = ca(oh)2
gives Nh3 , water and cacl2

Y = NaOH
gives Nh3 , water and Z = Na2s04

Question 14

Very pure N2 can be obtained by

Answer 14

Na or
Ba(N3)2 = Ba + 3 N2

Question 14

when ammonia reacts with water, it gives an alkaline X
i ) when X reacts with Y = brown ppt Z + chloride
ii) X + N = white ppt C + aq soln of G

Answer 14

X = Nh4oh
Y = Fecl3
Z = fe203.xh20
amonium chloride

N = ammonium hydroxide
c + znoh2
G = nh4)2 so4

Question 15

thermal decomposition of X gives N2 gas , water and which other Cr compound?

Answer 15

Decomp of
(NH4)2Cr207 when heated.
Cr203

Question 16

habers process temperature = X
Delta h is =

Answer 16

X = 773 K
negative

Question 17

N2 reacts with oxgen at 2000k to form which gas

Answer 17

N2+ O2 = 2 No

Question 17

what ion reacts with ammonia to give deep blue complex D what white ppt reacts with ammonia to give a colourless complex R

Answer 17

cu2+ D = Cu)NH3)4 )2+ white ppt = agcl R = [ Ag(NH3)2]Cl

Question 18

Decomposition of urea initially gives salt X which on futher decomp gives 2 gases and water . name all

Answer 18

URea Nh2CoNH2 = (NH4)2CO3 = 2NH3 + H20 + Co2

Question 18

catalyst in harbers process

Answer 18

Al203 + K20 iron oxide

Question 19

Nh4no3 decomposes to form which gas and what is its oxidation state

Answer 19

N20 +1

Question 20

2Nano2+ 2feso4 + 3 H2so4 gives which ferrous salt ii) this salt when reacts with Nahso4 gives which gas what is its oxidation state iii ) this gas produced when heated with N204 gives which other gas which what colour and acidic

Answer 20

Fe2(so4)3 the gas is NO the last gas is N203

Question 21

how many single bonds of N0 and double bonds between NO in N203

Answer 21

Sb = 1 Db = 2

Question 21

which compound F decomposes to give Pb0 + gas R + another gas ( combustible ) ii) this gas R when cooled gives gas D which reacts with NO to give a blue acidic gas E

Answer 21

F = Pb(No3)2 ( high temp 673 ) R = NO2 02 this is brown colour and acidic D = N204 E = N2o3 N204 and NO2 are in thermal equi ( reversible )

Question 22

reaction of Nitric acid with compound X gives meta phosporic acid ( Hpo3) + gas y

Answer 22

X = P2(o)10 Y = N2o5 colourless and acidic

Question 23

which oxides of nitrogen has NN bond

Answer 23

N - N - 0 N20

Question 24

Number of N-O-N bonds N=O bonds and N-O bonds in N205

Answer 24

non = 1 n=o 2 n-o 2

Question 25

no of Single NO bonds and Double NO bonds in n204

Answer 25

Sb = 4 Db = 2

Question 26

why does NO2 dimerise

Answer 26

it contains odd number of valence electron , on dimerisation , it gets converted to stable N204 with even number of electrons.

Question 26

what is formed in heating of chile saltpetre with conc

Answer 26

Hno3 and Nahso4

Question 26

xCu + y dil Hno3 = x ( Z ) + gas U I) what happens ( what gas is produced) when Cu reacts with conc hno3 ,

Answer 26

3 cu 8 hno3 3 Cu(no3) 2 + 2 NO i ) when cu reacts with conc hno3, it give No2 gas

Question 27

upon catalytic oxidation of gas A stoichimetrically in 1:t ratio with oxigen , with what catalyst, NO is formed.

Answer 27

A = Ammonia t = 5 pt/ru gauge catalyst

Question 27

nitric onxide ( no ) combines with o2 to give X i ) this X dissolves in water to give which acid + which other gas

Answer 27

X = No2 dissoves in water to give Hno3 + NO ( which was the maker of this gas initally )

Question 27

reaction of I2 with excess of Hno3 ( 10 hno3 ) = x + y ( gas ) ii) reaction with carbon = U + y gas iii ) reaction of 1 mole of S8 with d moles of Hno3 gives which acid and which gas iv) reaction of 1 P4 with how many moles of nitric acid , gives what compound , and what gas

Answer 27

HIO3 + 10 NO2 ii) Co2 + NO2 ( both gases ) iii) D = 48 gives H2so4 and gas No2 iv ) 20 moles of hno3 = gives = 4H3po4 + 20 NO2

Question 28

brown ring test depends on ability of what to what

Answer 28

fe2+ to reduce nitrates to nitric oxide which reacts with fe2+

Question 28

when Zn reacts with hno3, what is the compound formed and gas in - i ) dil hno3 ii) conc hno3

Answer 28

compound formed Zn(no3)2 i) dil = N20 ii) conc hno3 = No2

Question 29

reactions of brown ring test

Answer 29

no3- + fe2+ + 4H+ = No + 3 Fe3+ ii) fe(h20)6]2+ + NO = fe(h20)5No]2+

Question 30

what happens when dilute feso4 is added to added to no3- and then addind conc h2s04 along the side of the test tube. at what interface is the bronw ring formed

Answer 30

brown ring is formed at the interface of solution and h2s04 indicates the presecence of NO3-