List of practice Questions

The value of ($\Delta H - \Delta E$) for the reaction $C_6H_6(1) + 7\frac{1}{2} O_2(g) \rightarrow 6CO_2(g) + 3H_2O(I)$ at 270C is (R = 2 cal K-1 mol-1)

If the unit of force and length are doubled, the unit of energy will be

A particle of mass $m$ and charge $q$ with an initial velocity $v$ is subjected to a uniform magnetic field $B$ along the vertical direction. The particle will

An electric dipole consists of two opposite charges each 0.05 $\mu$C separated by 30 mm. The dipole is placed in an uniform external electric field of $ 10^6 \, NC^{ - 1}$. The maximum torque exerted by the field on the dipole is

A particle of mass m is moving along the x-axis under the potential $V (x) = \frac{kx^2}{2} + \frac{\lambda}{x}$, where $k $ and $\lambda$ are positive constants of appropriate dimensions. The particle is slightly displaced from its equilibrium position. The particle oscillates with the angular frequency $\omega$ given by

A stone falls freely from rest from a height $h$ and it travels a distance $\frac{9h}{25}$ in the last second. The value of $h$ is

Choose the weak monobasic acid, among the following

Identify the mismatched pair from the following

In petrochemical industry, alcohols are directly converted to gasoline by passing over heated

The wavelength of a 1 keV photon is 1.24 nm. The frequency of 1 MeV photon is:

Primary, secondary and tertiary alcohols can be distinguished by

A voltage $V_{PQ} = V_0 \, \cos \, \omega t$ (where $V_0$ is a real amplitude) is applied between the points P and Q in the network shown in the figure. The values of capacitance and inductance are $C = \frac{1}{\omega R \sqrt{3}}$ and $L = \frac{R \sqrt{3}}{\omega}$ Then, the total impedance between P and Q is

In alkaline medium $ Cl{{O}_{2}} $ oxidizes $ {{H}_{2}}{{O}_{2}} $ to $ {{O}_{2}} $ and itself gets reduced to $ C{{l}^{-}} $ . How many moles of $ H_20_2 $ are oxidized by 1 mole of $ Cl{{O}_{2}} $ ?

For signal transmission, modulation is necessary

The length of a rubber cord is $ {{l}_{1}} $ metre when the tension is $ 4\, N $ and $ {{l}_{2}} $ metre when the tension is $ 6\, N $ . The length when the tension is $9\,N$, is

The reaction of propene with $HBr$ in peroxide proceeds through the intermediate

Two planets have radii $r_1$ and $r_2$ and densities $d_1$ and $d_2$ respectively. Then the ratio of accelerations due to gravity on them is

Glucose does not react with

Consider the following antibiotics (i) Erythromycin (ii) Ofloxacin (iii) Chloramphenicol (iv) Penicillin (v) Tetracycline. The pair of bactericidal antibiotics is

A pendulum of length 1 m is released from $\theta$ = 60$^{\circ}$. The rate of change of speed of the bob at $\theta$= 30$^{\circ}$ is $(g=10 \, ms^{-1})$

A solution of methanol in water is $20\%$ by volume. If the solution and pure methanol have densities of $0.964 \; kg \; L^{-1}$ and $0.793 \; kg \; L^{-1}$, respectively, find the percent of methanol by weight?

A die has four blank faces and two faces marked $3$. The chance of getting a total of $12$ in $5$ throws is

If $a_1, a_2 , a_3 , a_4$ are in A.P., then $\frac{1}{\sqrt{a_{1}}+\sqrt{a_{2}}}+\frac{1}{\sqrt{a_{2}}+\sqrt{a_{3}}}+\frac{1}{\sqrt{a_{3}}+\sqrt{a_{4}}}=$

If $ \alpha $ and $ \beta $ are the roots of the equation $ a{{x}^{2}}+ $ $ bx+c=0,\text{ }\alpha \beta =3 $ and $a, b, c$ are in $A.P.$, then $ \alpha +\beta $ is equal to

A weak monobasic acid is 1% ionized in 0.1 M solution at $ 25{}^\circ C $ . The percentage of ionisation in its 0.025 M solution is