Which of the following alkyl halide will undergo \(\mathrm{S}_{\mathrm{N}} 1\) reaction fastest?

The reagents involved in the following conversion are

Ultra pure silicon can be obtained by

For a reaction
\(2A + B_{2} \rightarrow 2A_{2}B\)
The reactant A will be consumed at:

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Carboxylic acids are the earliest organic compounds isolated from nature. These are also known as organic acids but are weaker acids as compared to mineral acids. However, they are more acidic than alcohols and phenols because of greater resonance stabilization of the parent acid and its conjugate base. The acidic strength is determined by the \(K _a\), which is called the acidity constant.
The greater the value of \(K _a\), the greater the tendency of the acid to ionize and hence the stronger the acid. The acidic strength of the saturated aliphatic carboxylic acid depends upon the inductive effect and its position with respect to - COOH groups. Electron -donating substituents tend to decrease whereas electron-withdrawing substituents tend to increase the acidic strength. The acidic strength of the aromatic carboxylic acid, on the other hand depends upon both the inductive effect and the resonance effect of the substituents.
Arrange the following acids in decreasing order of acidity
(A) \(CH _3 CH _2 OH\)
(B) \(CH _3 COOH\)
(C) \(BrCH _2 COOH\)
(D) \(C _6 H _5 CH _2 COOH\)
Choose the correct answer from the options given below:

Arrange the following compounds in the order of their increasing boiling point :
Pentan-1-ol, n-butane, pentanal, ethoxy ethane

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Amines are considered as derivatives of ammonia obtained by replacement of hydrogen atoms with alkyl or aryl groups. In nature they occur among proteins, vitamins, alkaloids and hormones. These can be primary, secondary or tertiary depending on the number of hydrogen groups replaced. They can be prepared from nitro compounds, alkyl halides, nitriles, amides etc. Due to unshared pair of electrons they behave as Lewis bases. Influence of the number of hydrogen atoms at nitrogen atom is displayed in physical properties such as solubility, boiling point and chemical reactions including basicity. Basic character of amines is expressed in terms of their \(K_b\) and \(p K_b\) values. Three classes of amines can be distinguished with p-toluene sulphonyl chloride which reacts with primary and secondary ddu amines. Amino group when attached to benzene ring behaves as an activating and ortho para directing group.
Which reagent is used for the conversion of acetamide into ethylamine?

The beetle used as a biocontrol agent for aphids and mosquitoes is:

Match List - I with List - II.

List – I	List – II
(A) Polyvinyl chloride	(I) Phenol formaldehyde
(B) Urea-formaldehyde	(II) Ethyleneglycol and phthalic acid
(C) Glyptal	(III) Vinyl chloride
(D) Bakelite	(IV) Urea-formaldehyde

Choose the correct answer from the options given below :

Match List - I with List - II.

List - I	List - II
(A) Oxidation of primary alcohol to Aldehyde	(I) Concentrated sulphuric acid
(B) Oxidations of primary alcohol to carboxylic acid	(II) Zn. dust
(C) Dehydration of propanol to propene	(III) \(CrO _3\) in anhydrous medium
(D) Phenol to benzene	(IV) Acidified potassium permanganate

Choose the correct answer from the options given below :

Read the passage carefully and give the answers to the question :
Does the number of species in a community really matter to the functioning of the ecosystem? This is a question for which ecologists have not been able to give a definitive answer. For many decades, ecologists believed that communities with more species, generally, tend to be more stable than those with less species. According to the International Union for Conservation of Nature and Natural Resources (IUCN) (2004), the total number of plant and animal species described so far is more than 1.5 million.
The following are the various hypotheses proposed in explaining the greatest biological diversity in tropics except :

If \(A\) is a non-singular matrix of order 3 such that \(|\operatorname{adj}(A)|=121\), then \(\left|A A^T\right|\) is equal to :

\(\int \sqrt{1+\frac{x^2}{9}} d x\) is equal to
(Where \(C\) is an arbitrary constant)