The incorrect statement about rubber is :

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One of the notable features of the transition element is the great variety of oxidation states it may show in its compounds. The elements which give the greatest number of oxidation states occur in or near the middle of the series. Manganese, for example exhibits all the oxidation states from 2 to +7. The lesser number of oxidation states at the extreme ends is either due to losing or sharing of few electrons (Se, Ti) or too many d electrons of higher valence. Early in the first series scandium (II) is virtually unknown and titanium (IV) which is more stable than Ti (III) or Ti (II). On the other end, the only oxidation state of zinc is \(+ 2\).
Ambidentate ligand among the following is
A. NCS
B. \(C _2 O _4^{2-}\)
C. SCN
D. \(H _2 NCH _2 CH _2 NH _2\)
E. \(NO _2\)
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Which type of isomerism is shown by the complex compounds?
\(\left[ Co \left( NH _3\right)_5 Br \right] SO _4\) and \(\left[ Co \left( NH _3\right)_3 SO _4\right]\)Br

\(\text{CH}_3-\text{CH}(\text{Br}) - \text{CH}_2 - \text{CH}_3 \xrightarrow{\text{alc. KOH}} \text{A} \xrightarrow{\text{Br}_2} \text{CH}_3-\text{CH}(\text{Br}) - \text{CH}(\text{Br}) - \text{CH}_3 \text{(B)}\)
\(\text{(B)} \xrightarrow{\text{alc. KOH}} \text{CH}_3-\text{C} = \text{C} – \text{CH}_3 \text{(C)}\)
\(\text{(C)} \xrightarrow{\text{Hg}^{2+}/\text{H}^+\atop \text{H}_2\text{O}} \text{D}\)
A and D respectively are :

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Aldehydes and ketones represent two essential classes of organic compounds which are extensively used in the synthesis of a wide variety of other organic molecules.
Due to the inherent polarity of the central carbonyl group, these substances readily undergo nucleophilic addition reactions.Broadly speaking, these addition reactions can be categorized into two types:
one in which simple addition of the nucleophilic reagent occurs across the \(> C = O\) bond, and the second type where the initial addition is subsequently followed by the elimination of a water molecule.
A variety of ammonia derivatives, including hydroxylamine, hydrazine, phenylhydraaine, 2, 4-dinitroplhenylhdrazine, and semicarbazide, all belong to this second category of reactions.
These specific derivatives are fundamentally used for the identification and definitive characterization of aldehydes and ketones. Significantly, both types of nucleophilic addition reactions are strongly influenced by both steric and electronic factors.
As a general rule, aliphatic aldehydes exhibit higher reactivity compared to aromatic aldehydes.
The aliphatic aldehydes demonstrate the ability to reduce both Fehling's solution and Tollen's reagent, whereas aromatic aldehydes are limited to reducing only Tollen's reagent.
In a similar manner to aldehydes, aromatic ketones are observed to be less reactive than aliphatic ketones towards all nucleophilic addition reactions.
In a separate context, phenols and carboxylic acids both exhibit acidic properties in nature.
Both classes of compounds readily dissolve in NaOH solution and cause blue litmus to turn red.
However, carboxylic acids stand out as much stronger acids than phenols and thus can decompose sodium bicarbonate \(\left( NaHCO _3\right)\) with the distinct evolution of \(CO _2\) gas, a reaction which phenols do not undergo.
It is important to note that both electron- donating and electron- withdrawing substituents significantly influence the acid strength of both aliphatic as well as aromatic carboxylic acids.
Furthermore, unlike all other common aliphatic acids, formic acid uniquely possesses reducing properties and simultaneously does not display the typical reactions characteristic of the alkyl group.
Carboxylic acid do not give the characteristic reaction of carbonyl group because:

What is the IUPAC name of the product of hydration of propene in the presence of dilute sulphuric acid?

Match List - I with List - II.

List – I	List – II
(A) Glycosidic linkage	(I) Monomeric units of nucleic acid
(B) Peptide linkage	(II) Sugar-heterocyclic base combination
(C) Nucleotide	(III) Linkage between two amino acid units
(D) Nucleoside	(IV) Linkage between two mono saccharide units

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The corner points of the feasible region of the LPP: Minimize \(Z=-50 x+20 y\) subject to
\(2 x-y \geq-5,3 x+y \geq 3,2 x-3 y \leq 12\) and \(x, y \geq 0\) are:

If \(A=\left[a_{i j}\right]_{2 \times 2}\) where \(a_{i j}=\left\{\begin{array}{ll}1, & i \neq j \\ 0, & i=j\end{array}\right.\) and \(I\) is the identity matrix of order 2 , then \(\left(A^2-3 A+4 I\right)\) is:
(A) Symmetric Matrix
(B) Skew-symmetric Matrix
(C) Non-singular Matrix
(D) Square Matrix
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The area of the region bounded by the curve \(y=\sqrt{a^2-x^2}\) and \(x\) - axis included between the lines \(x=0\) and \(x=a\) is

Three resistors, each of resistance R, are arranged in the following different combinations with a source of emf E. Arrange them in the decreasing order of power dissipation:
(A) Three resistors in series
(B) Three resistors in parallel
(C) One resistor in series with two resistors in parallel
(D) One resistor in parallel with two resistors in series
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Observe the figures and answer the question.

The correct sequence for parts labelled (i), (ii), (iii) and (iv) in the figure is:
A. Plumule
B. Suspensor
C. Cotyledons
D. Radicle
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The equation of the normal to the curve \(y=2 \sin x\) at \((0,0)\) is: