List of top Chemistry Questions

Match List l with List ll.

List I Natural amino acid	List II One letter code
(I) Glutamic acid	(a) Q
(II) Glutamine	(b) W
(III) Tyrosine	(c) E
(IV) Tryptophan	(d) Y

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The statement/s which are true about antagonists from the following is/are:
A. They bind to the receptor site.
B. Get transferred inside the cell for their action.
C. Inhibit the natural communication of the body.
D. Mimic the natural messenger.
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The product (P) formed from the following multistep reaction is:

At constant temperature, a gas is at a pressure of 940.3 mm Hg. The pressure at which its volume decreases by 40% is mm Hg. (Nearest integer)

The descending order of acidity for the following carboxylic acid is-
A. CH₃COOH
B. F₃C-COOH
C. CICH₂-COOH
D. FCH₂-COOH
E. BrCH₂-COOH
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The correct order of reactivity of following haloarenes towards nucleophilic substitution with aqueous NaOH is 

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The correct IUPAC nomenclature for the following compound is.

The number of bent-shaped molecule(s) from the following is_______? 
SO₂, O₃, I₃^-, N₃^-

The Sum of number of lone pairs in central atom in IF₅ and IF₇ is:

In the following reactions, the total number of oxygen atoms in X and Y is _______
Na₂O + H₂O → 2X
Cl₂O₇ + H₂O → 2Y

Major product 'P' formed in the following reaction is:

Which of these reactions is not a part of breakdown of ozone in stratosphere?

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Sodium is about 30 times as abundant as potassium in the oceans.
Reason R : Potassium is bigger in size than sodium.
In the light of the above statements, choose the correct answer from the options given below

In Hall - Heroult process, the following is used for reducing Al₂O₃ :-

Henry Moseley studied characteristic X-ray spectra of elements. The graph which represents his observation correctly is
Given v = frequency of X-ray emitted
Z = atomic number

Lime reacts exothermally with water to give ‘A’ which has low solubility in water. Aqueous solution of ‘A’ is often used for the test of CO2 , a test in which insoluble B is formed. If B is further reacted with CO2 then soluble compound is formed ‘A’ is

The correct reaction profile diagram for a positive catalyst reaction .

Arrange the following gases in increasing order of van der Waals constant 'a'
A. Ar
B. CH4
C. H₂O
D. C6H6
Choose the correct option from the following.

Identify the correct order of reactivity for the following pairs towards the respective mechanism




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Molar mass of the hydrocarbon (X) which on ozonolysis consumes one mole of O3 per mole of (X) and gives one mole each of ethanal and propanone is _______ g mol-1  
(Molar mass of C : 12 g mol-1 , H : 1 g mol-1)

The titration curve of weak acid vs. strong base with phenolphthalein as indictor is shown below. The K_{phenolphthalein} = 4 × 10^-10 . 
Given: log2 = 0.3

The number of following statements which is/are correct about phenolphthalein is______
A. It can be used as an indicator for the titration of weak acid with weak base.
B. It begins to change colour at pH = 8.4
C. It is a weak organic base
D. It is colourless in acidic medium.

The number of following statement/s which is/are\(\text{\underline{ incorrect}}\) is______  
(A) Line emission spectra are used to study the electronic structure  
(B) The emission spectra of atoms in the gas phase show a continuous spread of wavelength from red to violet  
(C) An absorption spectrum is like the photographic negative of an emission spectrum  
(D) The element helium was discovered in the sun by spectroscopic method.

Three bulbs are filled with CH4, CO2 and Ne as shown in the picture. The bulbs are connected through pipes of zero volume. When the stopcocks are opened and the temperature is kept constant throughout, the pressure of the system is found to be_______atm. (Nearest integer)

In chromyl chloride, the number of d-electrons present on chromium is same as in (Given at no. of Ti : 22, V : 23, Cr : 24, Mn : 25, Fe : 26)

Match List-I with List-II :

	List-I		List-II
A	Saccharin	I	High potency sweetener
B	Aspartame	II	First artificial sweetening agent
C	Alitame	III	Stable at cooking temperature
D	Sucralose	IV	Unstable at cooking temperature

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