List of practice Questions

The molecular formula of diphenyl methane, \( \text{C}_{13}\text{H}_{12} \), is \( \text{C}_{13}\text{H}_{12} \). How many structural isomers are possible when one of the hydrogens is replaced by a chlorine atom?

Calculate the enthalpy change for the change \( \text{S}_8(g) \rightarrow \text{S}_g(g) \), given that: \[ H_2S_2(g) \rightarrow 2H(g) + 2S(g), \quad \Delta H = 239.0 \, \text{kcal/mol} \] \[ H_2S(g) \rightarrow 2H(g) + S(g), \quad \Delta H = 175.0 \, \text{kcal/mol} \]

Which of the following is best method for reducing 3-bromopropanal to 1-bromopropane?

Which one of the following has an optical isomer?

An element occurring in the bcc structure has \( 12.08 \times 10^{23} \) unit cells. The total number of atoms of the element in these cells will be:

The major product of the following reaction is:

Compound ‘A’ of molecular formula \( C_6H_10O \) on treatment with Lucas reagent at room temperature gives compound ‘B’. When compound ‘B’ is heated with alcoholic KOH, it gives isobutene. Compound ‘A’ and ‘B’ are respectively:

The reagent(s) which can be used to distinguish acetophenone from benzophenone is (are):

In the extraction of Cu, the metal is formed in the Bessemer converter due to the reaction: \[ \text{Cu}_2S + O_2 \rightarrow 2Cu + SO_2 \] The correct equation is:

For which of the following systems at equilibrium, at constant temperature, will the doubling of the volume cause a shift to the right?

A body cools from 50.0°C to 49.9°C in 5s. How long will it take to cool from 40.0°C to 39.9°C? Assume the temperature of surroundings to be 30.0°C and Newton’s law of cooling to be valid:

Consider the junction diode is ideal. The value of current flowing through AB is:

A metal disc of radius 100 cm is rotated at a constant angular speed of 60 rad/s in a plane at right angles to an external field of magnetic induction 0.5 Wb/m\(^2\). The emf induced between the centre and a point on the rim will be:

Ionisation energy of \( \text{He}^+ \) is \( 19.6 \times 10^{-18} \, \text{J} \, \text{atom}^{-1} \). The energy of the first stationary state (n = 1) of \( \text{Li}^{2+} \) is:

The chirality of the compound:

Which of the following compounds is formed when a mixture of \( K_2Cr_2O_7 \) and NaCl is heated with conc. \( H_2SO_4 \)?

For the process \( H_2O(g) \, (1 \, \text{bar}, 373 \, \text{K}) \rightarrow H_2O(g) \, (1 \, \text{bar}, 373 \, \text{K}) \), the correct set of thermodynamic parameters is:

In the circuit shown the cells A and B have negligible resistances. For \( V_A = 12 \, \text{V} \), \( R_1 = 500 \, \Omega \) and \( R = 1000 \, \Omega \), the galvanometer \( G \) shows no deflection. The value of \( V_B \) is:

A steel wire of length \( \ell \) has a magnetic moment \( M \). It is then bent into a semicircular arc. The new magnetic moment is:

A running man has half the kinetic energy of that of a boy of half his mass. The man speeds up by 1m/s so as to have same K.E. as that of the boy. The original speed of the man will be:

In Young's double slit experiment the two slits are illuminated by light of wavelength 5890Å and the distance between the fringes obtained on the screen is 0.2 cm. If the whole apparatus is immersed in water then the angular fringe width will be \( \dfrac{4}{3} \). The refractive index of water is:

Four point charges \( -Q, -2Q, 2q \) and \( 4q \) are placed, one at each corner of the square. The relation between \( Q \) and \( q \) for which the potential at the centre of the square is zero is:

In the given circuit the reading of voltmeter \( V_1 \) and \( V_2 \) are 300 volt each. The reading of the voltmeter \( V_3 \) and ammeter \( A \) are respectively:

The ratio of radii of the first three Bohr orbits is:

The given electrical network is equivalent to: