Chemistry
Two statements are given below :
Statement I : In H atom, the energy of $2 s$ and $2 p$ orbitals is same.
Statements II : In He atom, the energy of $2 s$ and $2 p$ orbitals is same.
The correct answer is
Assertion (A) : The ionic radii of $\mathrm{Na}^{+}$and $\mathrm{F}^{-}$are same.
Reason (R) : Both $\mathrm{Na}^{+}$and $\mathrm{F}^{-}$are isoelectronic species.
The correct answer is
Observe the following reaction,
$ 2 \mathrm{KClO}_{3}(s) \xrightarrow{\Delta} 2 \mathrm{KCl}(\mathrm{~s})+3 \mathrm{O}_{2}(\mathrm{~g}) $
In this reaction
What are $X$ and $Y$ respectively in the following reactions ?
$ X \stackrel{\mathrm{CO}}{\longleftarrow} \mathrm{~B}_{2} \mathrm{H}_{6} \xrightarrow[\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \mathrm{O}]{\mathrm{NaH}} Y $
Which of the following statements are correct?
(i) $\mathrm{CCl}_{4}$ undergoes hydrolysis easily
(ii) Diamond has directional covalent bonds
(iii) Fullerene is thermodynamically most stable allotrope of carbon
(iv) Glass is a man-made silicate
The correct answer is
The alkane which is next to methane in homologous series can be prepared from which of the following reactions?
$ \text { I. } 2 \mathrm{CH}_{3} \mathrm{Br} \xrightarrow[\text { Dry ether }]{\mathrm{Na}} $
II. $\mathrm{CH}_{3} \mathrm{COOH} \xrightarrow[\mathrm{CaO}, \Delta]{\mathrm{NaOH}}$
III. $\mathrm{CH}_{3} \mathrm{CH}=\mathrm{CH}_{2} \xrightarrow{\mathrm{H}_{2} / \mathrm{Pt}}$ IV. $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{Br} \xrightarrow[\mathrm{H}^{+}]{\mathrm{Zn}}$
What is ' $ Y $ ' in the following set of reactions?
$$ \mathrm{C}_3 \mathrm{H}_4 \xrightarrow[\substack{\mathrm{Hg}^{2+} / \mathrm{H}^{+} \\ 333 \mathrm{~K}}]{\mathrm{H}_2 \mathrm{O}} X \xleftarrow[\substack{\text { (ii) } \mathrm{Zn}+\mathrm{H}_2 \mathrm{O}}]{\text { (i) } \mathrm{O}_3} Y $$
Two statements are given below.
Statement I : Molten NaCl is electrolysed using Pt electrodes. $\mathrm{Cl}_{2}$ is liberated at anode.
Statement II : Aqueous $\mathrm{CuSO}_{4}$ is electrolysed using Pt electrodes. $\mathrm{O}_{2}$ is liberated at cathode.
The correct answer is
Observe the following reactions (unbalanced)
$ \begin{array}{r} \mathrm{P}_{2} \mathrm{O}_{3}+\mathrm{H}_{2} \mathrm{O} \longrightarrow X \\ \mathrm{P}_{4} \mathrm{O}_{10}+\mathrm{H}_{2} \mathrm{O} \longrightarrow Y \end{array} $
The number of $\mathrm{P}=\mathrm{O}$ bonds present in $X, Y$ are respectively
Arrange the following in increasing order of their crystal field splitting energy
I. $\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
II. $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$
III. $\left[\mathrm{Co}(\mathrm{CN})_{6}\right]^{3-}$
IV. $\left[\mathrm{CoF}_{6}\right]^{3-}$
What are ' $X$ ' and ' $Y$ ' respectively in the following reactions ?
Two statements are given below :
I. Milk sugar is disaccharide of $\alpha$-D-galactose and $\beta$-D-glucose
II. Sucrose is disaccharide of $\alpha$-D-glucose and $\beta$-D-fructose
The effects that aspirin can produce in the body are
Anti-Inflammatory | Anti-depressant | Anti-pyretic | Anti-coagulant | Hypnotic |
A | B | C | D | E |
The reagent ' $X$ ' used in the following reaction to obtain good yield of the product is
IUPAC name of the following compound is
The bromides formed by the cleavage of ethers $A$ and $B$ with HBr respectively are
Identify the set, in which $X$ and $Y$ are correctly matched
What are $X$ and $Y$ respectively in the following reactions?
Mathematics
$A=\left[a_{i j}\right]$ is a $3 \times 3$ matrix with positive integers as its elements. Elements of $A$ are such that the sum of all elements of each row is equal to 6 and $a_{22}=2$.
If $\mathrm{a}_{i j}=\left\{\begin{array}{cl}\mathrm{a}_{i j}+\mathrm{a}_{j i}, & j=i+1 \text { when } i < 3 \\ \mathrm{a}_{i j}+\mathrm{a}_{j i}, & j=4-i \text { when } i=3\end{array}\right.$ for $i=1,2,3$, then $|\mathrm{A}|=$
If $\omega$ is the complex cube root of unity and
$\left(\frac{a+b \omega+c \omega^{2}}{c+a \omega+b \omega^{2}}\right)^{k}+\left(\frac{a+b \omega+c \omega^{2}}{b+a \omega^{2}+c \omega}\right)^{l}=2$, then $2 k+l$ is always
With respect to the roots of the equation $3 x^{3}+b x^{2}+b x+3=0$, match the items of List I with those fo List II
List I | List II |
A All the roots are negative. | I. $(b-3)^2=36+P^2$ for $P \in R$ |
B Two roots are complex. | II. $-3<b<9$ |
C Two roots are positive. | III. $b \in(-\infty,-3) \cup(9, \infty)$ |
D All roots are real and | IV. $b=9$ |
V. $b=-3$ |
Assertion (A) : $1+\frac{2 \cdot 1}{3 \cdot 2}+\frac{2 \cdot 5}{3 \cdot 6} \frac{1}{4}+\frac{2 \cdot 5 \cdot 8}{3 \cdot 6 \cdot 9} \frac{1}{8}+\ldots \infty=\sqrt[3]{4}$
Reason (R) : |x| < 1,(1-x) $=1+n x+\frac{n(n+1)}{1 \cdot 2} x^2$$+\frac{n(n+1)(n+2)}{1 \cdot 2 \cdot 3} x^{3}+\ldots$
The correct answer is :
$\mathbf{a}$ is a vector perpendicular to the plane containing non zero vectors $\mathbf{b}$ and $\mathbf{c}$. If $\mathbf{a}, \mathbf{b}, \mathbf{c}$ are such that
$|\mathbf{a}+\mathbf{b}+\mathbf{c}|=\sqrt{|\mathbf{a}|^{2}+|\mathbf{b}|^{2}+|\mathbf{c}|^{2}}$, then
$|(\mathbf{a} \times \mathbf{b}) \cdot \mathbf{c}|+|(\mathbf{a} \times \mathbf{b}) \times \mathbf{c}|=$
If $\int \frac{1}{x^{4}+8 x^{2}+9} d x=\frac{1}{k}$$\left[\frac{1}{\sqrt{14}} \tan ^{-1}(f(x))-\frac{1}{\sqrt{2}} \tan ^{-1}(g(x))\right]+c$ then,
$\sqrt{\frac{k}{2}+f(\sqrt{3})+g(1)}=$
The order and degree of the differential equation
$ \frac{d y}{d x}=\left(\frac{d^{2} y}{d x^{2}}+2\right)^{\frac{1}{2}}+\frac{d^{2} y}{d x}+5 \text { are respectively } $
Physics
A block is kept on a rough horizontal surface. The acceleration of the block increases from $6 \mathrm{~ms}^{-2}$ to $11 \mathrm{~ms}^{-2}$ when the horizontal force acting on it increases from 20 N to 30 N . The coefficient of kinetic friction between the block and the surface is
(acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )