1thanks debo for this useful info....
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** Only Q6 is more than one correct **
Q1 BeO +NaOH → ?
Q2 Which is used for fixing atmospheric nitrogen ?
a)nitrolim
b)Li3N
c)Mg3N2
d)all
I am sure abt a)..but not abt others..
Q3 BaC2 +N2 +heat → ??
Q4 CaC2 +N2 +heat → ??
I think it should be CaCN2 but ans is given Ca(CN)2
Q5 WHy is NaCl added during extraction of Mg from Magnesium chloride ?
Q6Acidic fluxes are
a)SiO2
b)borax
c)Fe2O3
d)CaCO3
Q7 Is there any general law or something that helps us to identify whther a compound is soluble in wate or not ???(just like fajans rule helps us in a lot of things)
*PLs dont state that line "Like dissolves like "* [3]
Q8 which is used to treat acid indigestion ?
a)Al4C3+H2O→CH≡CH
b)CaC2+H2O→CH≡CH
c)Mg4C3+H2O→CH3C≡CH
d)All true
I think ans should be b,c...but not sure..
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19 Answers
24thx all..
btw didnt want to start a new thread for just 2 ques,,adding here
Q9 which of the following cant be obtained by electrolytic reduction of their compounds in aqueous soln ??
a)Ba
b)Cd
c)K
d)Ni
Q10 fuel and ore are mixed and heated in
a)kiln
b)blast furnace
c)muffle furnace
d)reverbatory furnace
1i hv some doubts regarding Q.3) and Q.4).
actually , some points hv been made about the products that :
[N=C=N]2- + C → 2 (CN)2-
but , i don't think, this happens. as cyanamide ion([N=C=N]2-) is stable and doesn't co-exist in cyanide state.
so, BaC2 + N2 + heat → Ba(CN)2.
but , CaC2 + N2 + heat → Ca(N=C=N) + C
thus , CaC2 forms cyanamide but not BaC2.
this calcium cyanamide is known as nitrolim. and this reaction is one of the reactions of nitrogen fixation. thus, this also gives the answer of Q.2 i.e. a).
rest of the options given are formed by reaction with N2 . thus, they 'll not further react.
Q.6) a) and b)
Q.8) The answer is b,c only.
as reaction a) is incorrect. hydrolysis of Aluminium carbide forms methane gas not acetylene.
24ya arshad was rite...i misread his ans...actually same ans was given in my book too....so my book isnt wrong too...[3][3]No need for doctor debo
19arshad is absolutely correct in answer (5)......sodium chloride lowers the fusion temperature of MgCl2 and makes the mixture a good conductor of electricity !!! thats it,,,nothing else !!! @eureka...you get your questions' source treated by a doctor, very well,almost 2 out of 3 answers are wrong !!! thats strange!!! don't mind this , dude !!! [3][3]
1Many books give the formula of Nitrolim as Ca(CN)2 , which is actually CaNCN + C .
So in qs. 4 , you are correct .
24thx for all answers..
@arsahd ans 5 is rong...
and plz i need something concrete for Q7 (if exists)
also i added a ques8 here
1for question 5-i think it is added to increase conductivity and make it melt at lower temperature.....
1All chlorates and all sulphates are also soluble (CaSO4 and AgSO4 are slightly soluble)
All bromides and chlorides (except AgCl and AgBr) are also soluble
1qs . 3 > BaNCN + C
en.wikipedia.org/wiki/Barium - Cached - Similar
1q)1 [Be(OH)4]2- + Na+
q)2 all ie.d option
proof for magnesium nitride
http://www.absoluteastronomy.com/topics/Magnesium_nitride
proof for lithium nitride
http://science.jrank.org/pages/4685/Nitrogen-Chemistry-compounds.html
q)3 BaCN2 +C
q)4 CaCN2 + C
q)6 borax and sio2 to sure hai...ie a and b
1Yeah , except Bismuth Oxy-Nitrate , all nitrates are soluble in water due to low hydration energy.
1q7 there is some funda like "all nitrates are soluble in water"...not sure about the reason...
other than that even i'm in search of a general law or sumthing..:)