Elements of group-15, 16 and 17 form compounds with hydrogen with general formula MH3, H2M and HX (called hydrogen halides). Stability of these hydrides, along with M-H bond strength and basic nature decreases down the group. Boiling point of these hydrides mainly depends on the strength of their inter molecular forces.
Which of the following is liquid at \(20^{\circ} C\) ?
A. HCl
B. HI
C. HF
D. NH3
E. HBr
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Zone refining is mainly used for :

With reference to D-glucose, which of the following
cannot be explained by its open chain structure?
(A) D-Glucose does not give Schiff's test.
(B) The pentaacetate of D-glucose does not react with hydroxylamine.
(C) Glucose is found to exist in two different crystalline forms.
(D) D-glucose reacts with mild oxidizing agents like \(\text{Br}_2\text{-H}_2\text{O}\)
and forms gluconic acid.
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Read the passage carefully and answer the Questions
The term vitamin was coined from the word vital +amine since the earlier identifiedc ompounds had amino groups. Later work showed that most of them didn't contain amino groups. They are very essential for the body. They has to be taken various diet or in the form of medicines also.
Vitamins are classified into two groups depending upon their solubility in water or fat.
Fat soluble vitamins are soluble in fat and oils but insoluble in water. They are stored in liver and adipose (fat storing) tissues Water-soluble vitamins are soluble in water. These must be supplied regularly in diet because they are readily excreted in urine and cannot be stored in our body.
What are the sources of Vitamin C?

The correct IUPAC name of tert-butyl benzyl ether is-

Match List - I with List - II

List - I	List - II
(A) Chloroxylenol + terpineol	(I) Antiseptic
(B) Penicillin	(II) Antibiotic
(C) Iproniazid	(III) Tranquillizer
(D) Aspirin	(IV) Analgesic

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The most unsymmetrical crystal system is

The magnetic moment in transition metals is calculated using the formula:

Which of the following cannot be explained by the open chain structure of glucose?

Match List I with List - II.

List-I (Transformer)	List-II
(A) Flux leakage	(I) Laminated core
(B) Energy loss due to resistance of winding	(II) By winding the primary and secondary one over the other
(C) Eddy current loss	(III) Using thick wires
(D) Hysteresis	(IV) By using soft iron core

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The decreasing order of basicity of following amines in aqueous phase ;
(A) N, N-Dimethylmethamine
(B) Methanamine
(C) N-Ethylethanamine
(D) Phenylmethanamine
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During allergic reactions, which of the followings are secreted?
(A) Histamines
(B) Interferons
(C) Serotonin
(D) Pyrogens
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Some strains of Bacillus thuringiensis produce toxic proteins that do not kill: