24@govind ...can u elaborate for Q6 plzz
**I am hiding the solved questions....**
1)Hydrolysis of PI3 gives ??
2)Decomposition of H2O2 is lowed down by addn of ??
3)compound which is used in space vehicels to absorb CO2 and liberate O2
a)NaOH
b)NaO
c)Na2O2
d)CaO and NaOH
4)Nitrogen is inert due to
a)high electronegativity
b)small atomic radius
c)high disocation energy
d)stable config
5)conc. HNO3 oxidises
a)H3PO4
b)P2O5
c)H3PO3
d)H4P2O7
6)Thermal stablity of polyhalides is ??
Na+,K+,Rb+,NH4+
7)Cl2 is dreid over
a)CaO
b)NaOH
c)H2SO4
d)HBr
-
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28 Answers
1064. C (it is due to triple bond... there are many molecules with stable config. ex. Na+ (it has full filled orbital) but it is extremely reactive)
5. C (all others have max oxdn state of +5 in P)
6. Thermal stablity of polyhalides is ??
Na+,K+,Rb+,NH4+
Polyhalides mein kabse Na+,K+ aane laga hai?
29In question 6..i used that funda..like that we have for peroxides..Li peroxide is not stable bcoz the charge density is not matchable and down the grp peroxides and superoxides become stable because the charge density is matchable...
similarly in this case I3- is a very big anion..so stability will increase down the grp..as down the grp charge density decreases..
29I took I3- here for comparison...coz the other polyhalides are very less stable..
137) "Anion" kya hai idhar...matlab talking about which halogen, so as 2 compare charge density....??
Also,how do v have a "Polyhalide" here...?
29oops..abt the position of NH4+ i was unsure...the concept is....thermally stable compounds are formed when there is a charge density matchability b/w the cations and anions...
24thx for Q5...it maybe misprint in ans key then..
ans2 is given as alcohol
ans6 is Na+ < K+ < NH4+< Rb+
xplain plzzzzzzzzzzzzzzzzzzz
29Ans 2 ...Urea or sodium Stannate..
Ans 5 ...H3PO3
Ans 6 .. Na+ < K+ < Rb+ < NH4+
1what is the answer given for q 2?i got my ans from wiki.
there might be quite a few answers for this..
29@Eureka..the flaw in post #5 is that.....Phosphorus has also the same config. 3s2 3p3 ..but it's very reactive as we know...So only reason for less reactivity of N2 is it's high bond dissociation energy..
49explanation for #5...why is it wrong!!
well N has a high ionization energy since it has got stable structure with half filled p orbitals!!
but as N is non metallic in nature, it has got negative electron gain enthalpy...hmm...even if it wer positive, the value would be not much!!
thus reactivity of a N atom, or any electron gaining species as such does not depend on the structure in case it is gaining its first electron
well the previous statement is just madre out of floating thoughts, may be wrong!!
24@asish....
kk.i got 4
ans 5 wrong
aur Q6 jaisa fiitjee ne likha ,maine vaisa hi likh diya.....main toh dumb hoon yaar
@arka
ans2,5 wrong
17. it has to be c)conc H2SO4,CaO and NaOH will react with Cl2 as they are basic and Cl2 is an acidic gas.
5. c)H3PO3 as in it P is in oxidation state +3 which can be increased.
4. c)as said by others earlier the triple bond in N2 molecule is difficult to break.
2. wikipedia It is usually stabilized with acetanilide(N-phenylacetamide),a substance that has toxic side-effects in significant amounts.
24kkk.....i dint have direct ans for that
option were of type .. one monobasic and 2 dibasic etc.....
494)
Nitrogen gas (dinitrogen) is chemically non-reactive at ordinary temperature due to:
* Its small atomic size.
* Its high bond order. The N-N bond in the N2 molecule has a formal triple bond character.
The NN bond is very stable. Its bond dissociation energy is 946kJ mol-1.
The dissociation constant is extremely small and even at 3000 K there is no appreciable dissociation. This indicates the strength of the N-N bond.
11Ans 3) (c) bcoz it reacts with CO2 in air, it removes both CO2 and produces O2.
2Na2O2 + 2 CO2 → Na2CO3 + O2
39Yes subho is right for Q7...actually some PHOSPHORUS compound is dried over CaO.
http://www.ucc.ie/academic/chem/dolchem/html/elem/elem017.html
It is dried by bubbling through conc H2SO4.
397) I think chlorine is dried over a packed tower of CaO, if I remember correctly...could be some other compound also.
49for 3) i think the most probable answer is a peroxide...the only given peroxide is Na2O2.
49for 5) it is conc. H2SO4...this is because with basic drying agents Cl2 undergoes neutralisation and with HBr it undergoes redox reaction!!
so left option is H2SO4
49for quest 4..
it is c)
high bond dissociation energy (due to TRIPLE bond)