List of practice Questions

Some of the properties of the two species, $NO _{3}^{-}$and $H _{3} O ^{+}$are described below. Which one of them is correct?
What is the value of electron gain enthalpy of $Na^+$ if $IE_1$ of $Na = 5.1 \,eV$ ?
In the following reaction, $C_6H_5CH_2Br \ce{->[{(i) \text{Mg,Ether}}][{(ii) H_3O^+}] X }$ the product ' $X$ ' is
Which has the maximum number of molecules among the following ?
Fructose reduces Tollen's reagent due to
Which of the following compound is the most basic ?
Some statements about heavy water are given below. (i) Heavy water is used as moderator in nuclear reactors (ii) Heavy water is more associated than ordinary water (iii) Heavy water is more effective solvent than ordinary water Which of the above statements are correct?
Which one of the following compounds will be most readily dehydrated ?
Which one of the following compounds will be most readily dehydrated ?
$A$ and $B$ are two metals with threshold frequencies $1.8 \times 10^{14}\, Hz$ and $2.2 \times 10^{4}\, Hz$ Two identical photons of energy $0.825 \,eV$ each are incident on them. Then photoelectrons are emitted by (Take $\left.h=6.6 \times 10^{-34} \,J - s \right)$
Two capacitors of capacities $1 \, \mu F$ and $C \, \mu F$ are connected in series and the combination is charged to a potential difference of $120 \,V$. If the charge on the combination is $80 \, \mu C$, the energy stored in the capacitor of capacity $C$ in $\mu J$ is
In the Wheatstone's network given, \(P = 10\,\Omega , Q = 20\,\Omega , R = 15 \,\Omega , S = 30 \,\Omega\), the current passing through the battery (of negligible internal resistance) is
Wheatstone's network
The potential of a large liquid drop when eight liquid drops are combined is 20 V. Then the potential of each single drop was
In hydrogen a atom, an electron is revolving in the orbit of radius $0.53\,�$ with $6.6 \times 10^{15}$ radiations/s. Magnetic field produced at the centre of the orbit is
In photoelectric emission process from a metal of work function $1.8 \,eV,$ the kinetic energy of most energetic electrons is $0.5 \,eV$. The corresponding stopping potential is
In the figure shown, the magnetic field induction as the point $O$ will be
A direct $X$ -ray photograph of the intenstines is not generally taken by radiologists because
The kinetic energy of an electron get tripled then the de-Broglie wavelength associated with it changes by a factor
A parallel plate capacitor has capacitance $C$. If it is equally filled the parallel layers of materials of dielectric constant $K_1$ and $K_2$ its capacity becomes $C_1$. The ratio of $C_1 $ and $C$ is
The maximum value of $4 \, \sin^2 \, x - 12 \sin \, x + 7$ is
If $A = \begin{bmatrix}1&-5&7\\ 0&7&9\\ 11&8&9\end{bmatrix}$, then trace of matrix $A$ is
If $(-3, 2)$ lies on the circle $x^2 + y^2 + 2gx + 2fy + c = 0$, which is concentric with the circle $x^2 + y^2 + 6x + 8y - 5 = 0,$ then c is equal to
The value of the determinant $\begin{vmatrix}\cos\alpha&-\sin\alpha&1\\ \sin \alpha&\cos\alpha&1\\ \cos\left(\alpha+\beta\right)&-\sin\alpha+\beta&1\end{vmatrix} $ is
A straight line through the point A(3, 4) is such that its intercept between the axes is bisected at A, its equation is
In the given circuit, the AC source has ? = 100 rad/s. Considering the inductor and capacitor to be ideal, the correct choice(s) is(are)