in inorganic chemistry questions are oftenly asked from S,p,d,f block elements

and there are questions from qualitative analysis(practical chemistry)

 

i m giving few questions from previous year iit papaers.

 

1)How is boron obtained from borax ? give chemical reaction with conditions. write the structure of B₂H₆ and its reaction with HCl. IIT-2002

  although the question is subjective bt now u'll c objective stuff..

2)which of the following compound is expacted to be coloured?

a) Ag₂SO₄    b) CuF₂     c)  MgF₂        d)  CuCl       IIT 1997

4 Structural isomers are possible

1) 3 isomers are producded by subsitution at either ortho meta or para position

2) 4th isomer is produced by by subsituting hydrogen of methane.

only 2 chiral compound obtained by following attacks.

CH₃CCl(CH₃)CH₂CH₃ chlorination at position 1.

CH₃CH(CH₃)CH(Cl)CH₃ chlorination at position 3.

 

so dear create burning desires for your goals....

P.S: time is precious use it properly.

sure y not...

let me tell u one story abt my friend ..he was with me in masters he flunked in masters and next year he cleared that exam and right nw he is university of wisconcin madison us for his phd program...

he has 25 research publications by his name..

since u have to find out oxidation state of Cr put Cr=X

Now calculate

x+ 3(-2)=-3

there fore x=+3     (-2 is the oxidation state of oxalate)

 bt dear u have to read that chapter properly.

for that u have to read a chapter called co-ordination chemistry.

few things are imp

1) sum of the oxidation states of a neutral complex is 0

2) sum of the oxidation state of a charged complex is equal to its charge it could be -ve or +ve.

3)read abt ligands like neutal ligand like NH₃ ,H₂O,NO,CO etc they have zero total oxidation state

4)negative ligands, they have total oxidation state equal to their total charge.

eg CL-,Br-

 now your example

[Cr(C₂O₄)₃]^3-

Its a negative complex so total oxidation state is equal to -3 thats the total charge.

if ur goin to prepare of iit-jee  than board course is like a drop in a ocean..

in coaching centres teacher help u to solve high level problems...at times some chapter r neglected or given less important in iits.....so these chapters u have to cover your self..bt they r nt that difficult that u have to take seprate coaching for that.....do rem u have to manage time..which is going to be the most imp factor... i have seen few students who join so many coachings bt couldn't make it to any thing...

P.S: self study is key to success

HI is stronger acid than HCl is because of heat of ionisation which is large for HI(63.8KJ/MOL) compared to HCl(59.8kj/mol)

HEAT OF IONIZATION : the energy released in ionization of 1 MOLE HX (X=HALOGEN)

HClO3 is stronger acid than HIO3 because as the electronegativity of the central atom X decreases as we move from CL to I , the tendency of the central atom to attract the electron pair of X-O bond towards itself decreases and hence the possibility of rupture of O-H bond decreases.

 

When we talk abt the thermal stability we consider ClO₄^-

ClO₃^- >ClO₂^- >ClO^-

and the reason is localization of -ve charge.

order of thermal stability is HClO>HClO₂>HClO₃>HClO4 its same as acidic nature.

order of oxidising strength is reverse.

 

OZONOLYSIS:

It comprises of 2 steps

1)addition of ozone

2)hrdrolysis of ozonide in the presence of reducing agent or oxidizing agent.

if we r using reducing agent(Zn-ACOH) then its reductive ozonolysis.

and if we r using oxidising agent(H₂O₂) then its oxidation ozonolysis .

the product that we get in oxidative analysis is carboxylic acid and ketone.