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in lucas test HCl is a weak acid and thus does not protonate the
-OH group enough. The lewis acid ZnCl2 coordinates with the -OH group and thus makes it a better leaving group.

During elimination we remove two table C-H bonds and then form a weak C-C pi-bond. This thus needs energy and thus the given energy is stored as intrinsic energy and destabilizes the molecule.

iT FORMS AN ADDITION PRODUCT i.e., salt.

RCHO undergoes rxn an forms [RCH(OH)(SO₃)]^-Na⁺.

All E1 rxns are not E1cb. all E1cb are E1.

The conditions for an E1 reaction are a polar solvent, good leavin grp i.e weak nucleophile(e.g F^-, Cl^-) .

It usually takes place when a stable carbocation is formed ( benzyl, 3 degree etc.)

E1cb has all these conditions and also apart from these it needs to have a very strong withdrawing group (e.g F^-) .

Lanthanides have the same outer electronic configuration, and the only change is in the anti penultimate shall. This is also in the f-orbitals thus due to their poor shielding effect the extra nuclear charge does not really have an effect on the outer shell.

Even the tri cyclo propyl methyl carbocation is not the most stable. There are many more exotic species. For one the acylinium ion.

Dear friend,

The answer to your question is the bent orbital concept. The ring strain in the cyclo propyl group is very high and thus the orbitals which are theoretically sp³hybridised are not ideally placed and are bent towards the outside of the ring. They thus behave like p-orbitals to some extent. they thus overlap with the empty p-orbital on the carbonium ion and thus open up the ring and relieve it of angle strain. This brings about enough stability for it to be more stable than the triphenyl carbocation itself!!!!!!!

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If we can gather enough opinions on this issue we can then probably find someone to raise the issue with the concerned people.

There always is a refractive index for a medium and also if you noticed all fields have to propogate as electromagnetic fields.

This is a question in AIEEE2008.

Q) The relative permittivity and permeability of a diamagnetic material are E and U respectively. Which of the following values are permissible?

A) E=1.5 U=0.5

B) E=1.5 U=1.5

C) E=0.5 U=1.5

D) E=0.5 U=0.5

The general answer given by all the insitutes is given as (A). But no one seems to be considering the fact that the refractive index of the medium has to be greater than 1 and thus EU>1.

There is no option in the question considering also the fact that U<1 for a diamagnetic material.

Is there any way i can point this out to the AIEEE board?

EDTA is used as a cream to treat dermatitis. It is a very strong complexing agent. Thus the calcium salt is also used to remove traces of any harmful metals as well.

Zr and Hf possess similar properties and not Zr and Hg as you asked. Also the reason is lanthanoid contraction.

Is there any way one can approach the AIEEE board to notify them that a question has no answer?

There is a question which I have already posed in the Electromagnetics related forum. I am pretty sure there is no answer. But then most of the solutions(of different institutes) donot seem to consider one very important fact.

This is in reference to a question in aieee2008.

Q) Relative permittivity and permeability of a material are E and U respectively. Which of the following values are allowed for a diamagnetic material.

1) E=0.5 U=0.5

2)E=0.5 U=1.5

3) E=1.5 U=1.5

4) E=1.5 U=0.5

The general answer in all solutions is (4), but if we consider the fact that refractive index of medium has to be greater than 1 and thus EU>1, the answer is only (3).

But there is no option in the question considering also the fact that U<1 for diamagnetic substance.