If time taken for a first order reaction to get \(90\%\) complete is \(24\ min\), its \(t_{99.9\%}\) will be:

Which of the following reagent is not used to convert aldehyde into alcohol?

Answer the question on basis of passage given below :
P block elements are placed in groups 13 to 18 of the periodic table. Their valence shell electronic configuration is \(ns^2 np^{1-6}\). Group 16 of the p block elements are known as the group of chalcogens having \(ns^2 np^4\) as their general electronic configuration. They exhibit number of oxidation states but the stability of \(- 2\) oxidation state decreases down the group. They are sometimes also known as group of chalcogens as the name is derived from the Greek word for brass and points to the association of sulphur and its congeners with copper. Their ionisation enthalpy decreases down the group. Oxygen shows anomalous behaviour due to its small size and high electronegativity.
Match the oxidation state of phosphorous in the following compounds to their counter parts in List II.

List - I (Compounds)	List - II (Oxidation States)
(A) \(H _3 PO _2\)(Hypophosphorous acid)	(I) +3
(B)\(H _4 P _2 O _6\)(Hypophosphoric acid)	(II) +5
(C) \(H _3 PO _3\)(Phosphorous acid)	(III) +1
(D)\(H _3 PO _4\)(Orthophosphoric acid)	(IV) +4

Choose the correct answer from the options given below :

"Wood spirit " is

A brown ring is formed in the ring test for \(NO _3^{-}\)ion. It is due to the formation of:

The conductivity of 0.001 mol \(\text{L}^{-1}\) acetic acid is \(5.01 \times 10^{-5} \text{ S cm}^{-1}\).
Calculate its dissociation constant if \(\Lambda_m^{\circ}\) for acetic acid is
390.5 \(\text{S cm}^2 \text{mol}^{-1}\).

Read the passage carefully and answer the Questions
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.
p-Nitrobenzoic acid is a stronger acid than benzoic acid because of

If \(\left|\begin{array}{cc}2 x & 5 \\ 8 & x\end{array}\right|=\left|\begin{array}{cc}3 & 0 \\ 4 & -8\end{array}\right|\), then value(s) of \(x\) is/are

From the following, choose the one which are not secondary haloalkanes :
(A) 2-Bromopentane
(B) 1-Bromo-3-methylbutane
(C) 3-Bromopentane
(D) 2-Bromo-2- methylbutane
(E) 2-Bromo-3-methylbutane
Choose the correct answer from the options given below :

The conversions which are represented correctly are
(A)

(B)

(C)

(D)

Choose the correct answer from the options given below:

In which process unusual nucleotide (methyl guanosine triphosphate) is added to the 5' end of hnRNA.

The window of the house is in the form of a rectangle surmounted by a semi-circular portion, having a perimeter of 10 m as shown in figure.

If \(x\) and \(y\) represent the length and breadth of rectangular region, then the area A of the window in terms of \(x\) is :

The digit in the unit's place of \(6^{500}\) is: