Recent questions tagged class12

Mole fraction of the component 'A' in vapour phase is X and mol fraction of component 'A' in liquid mixture is Y $(P_A^0$=vapour pressure of pure A,$P_A^0$=vapour pressure of pure B) then total vapour of the liquid mixture is

asked Feb 14, 2014 by sreemathi.v

1 answer

pH of a 0.1M monobasic acid is found to be 2.Hence its osmotic pressure at a given temp T is

asked Feb 14, 2014 by sreemathi.v

1 answer

At room temperature $25^{\large\circ}C$,the vapour pressure of pure methyl alcohol is 92 torr.Mol fraction of $CH_3OH$ in a solution in which vapour pressure of $CH_3OH$ is 24 torr at $25^{\large\circ}$ is ?

asked Feb 14, 2014 by sreemathi.v

1 answer

A point source of light is placed at the bottom of a tank containing a liquid $(R.I= \mu)$ upto a depth $h$. A bright circular spot is seen on the surface of the liquid. Then the radius of this bright spot.:

asked Feb 14, 2014 by meena.p

1 answer

At room temperature $25^{\large\circ}C$,the vapour pressure of pure methyl alcohol is 90 torr.Mol fraction of $CH_3OH$ in a solution in which vapour pressure of $CH_3OH$ is 20 torr at $25^{\large\circ}$ is ?

asked Feb 14, 2014 by sreemathi.v

1 answer

In the figure shown for an angle of incidence i at the top surface , What is the minimum refractive index needed for total internal reflection at vertical face ?

asked Feb 14, 2014 by meena.p

1 answer

Most likely the following mixtures to be an ideal solution is

asked Feb 14, 2014 by sreemathi.v

1 answer

At room temperature $25^{\large\circ}C$,the expression for total pressure of mixture of methanol and ethanol solution is given by P(in torr)$=135+120X$ where $X$ is mol fraction of methanol,Hence

asked Feb 14, 2014 by sreemathi.v

1 answer

A particle of mass m and charge +q is projected from the origin with a speed v at an angle $\;30^{0}\;$ with the horizontal into an electric field of intensity E directed downward . Equation of trajectory of particle is . Neglect gravity

asked Feb 14, 2014 by yamini.v

1 answer

When mercuric iodide is added to the aqueous solution of potassium iodide,the

asked Feb 14, 2014 by sreemathi.v

3 answers

Mixture of volatile components A and B has total vapour pressure (in torr) P=$250-115X_A$ where $X_A$ is mol fraction of 'A' in mixture.Hence $P_A^0$ and $P_B^0$ respectively are (in torr)

asked Feb 14, 2014 by sreemathi.v

1 answer

Which of the following azeotropic solutions has the boiling point less than the boiling point of the constituents

asked Feb 14, 2014 by sreemathi.v

1 answer

An azeotropic solution of two liquids has a boiling point lower than either of them when it

asked Feb 14, 2014 by sreemathi.v

2 answers

Which is true about enthalpy of solution containing benzene and toluene?

asked Feb 14, 2014 by sreemathi.v

1 answer

The degree of dissociation $'\alpha'$ of a weak electrolyte is (N is number of ions given by 1 mol of the electrolyte)

asked Feb 14, 2014 by sreemathi.v

1 answer

Which of the following has maximum freezing point for 1 molal solution, assuming equal ionisation in each case?

asked Feb 14, 2014 by sreemathi.v

1 answer

One mole each of the following solutes are taken in 1000g of water

asked Feb 14, 2014 by sreemathi.v

1 answer

Lowering of vapour pressure due to a solute in 1 molal aqueous solutions at $100^{\large\circ}C$ is

asked Feb 14, 2014 by sreemathi.v

1 answer

A particle of charge -q and mass m moves in a circle of radius r arround an infinitely long line charge of linear density $\;+\lambda\;$ . Then time period will be

asked Feb 14, 2014 by yamini.v

1 answer

Match the column-I with column-II ,which are true for 20% w/w aqueous KI solution (density of KI solution is 1.20g/ml & M.wt of KI is 166 g/mol)

asked Feb 14, 2014 by sreemathi.v

1 answer

Three concentric spherical metallic shells A , B and C of radii a , b and c $\;(a < b < c)\;$ have charge densities $\;\sigma , - \sigma \; and \; \sigma\;$ respectively . If the shells A and C are at the same potential then the relation between a , b and c is

asked Feb 14, 2014 by yamini.v

1 answer

Match the column-I and column-II

asked Feb 14, 2014 by sreemathi.v

1 answer

Which is true about ideal solutions?

asked Feb 14, 2014 by sreemathi.v

1 answer

Total vapour pressure of mixture of 1 mole $X(P_x^0=150torr)$ and 2 mol Y$(P_y^0=240torr)$ is 210mm.In this case

asked Feb 14, 2014 by sreemathi.v

1 answer

Mole fraction of the benzene in the vapour phase which is in equilibrium with a solution of benzene $(p^0=120torr)$ and toluene$(p^0=80torr)$ having 4.0mole of benzene and 6 mole of toluene in solution.

asked Feb 14, 2014 by sreemathi.v

1 answer

A 10.0 Kg block carrying a charge 100 $\;\mu C\;$ is connected to a spring for which $\;K=100 N/m\;$ . The block lies on a frictionless horizontal track , and the system is immersed in a uniform electric field $\;E=5\times10^{5}\;V/m\;$ , directed as shown in figure . If the block is released from rest when the spring is amount does the spring expand

asked Feb 14, 2014 by yamini.v

1 answer

Mole fraction of the benzene in the vapour phase which is in equilibrium with a solution of benzene $(p^0=120torr)$ and toluene$(p^0=80torr)$ having 2.0mole of each is

asked Feb 14, 2014 by sreemathi.v

1 answer

Mole fraction of the toluene in the vapour phase which is in equilibrium with a solution of benzene $(p^0=120torr)$ and toluene$(p^0=80torr)$ having 2.0mole of each is

asked Feb 14, 2014 by sreemathi.v

1 answer

A point charge q is placed on the top of a cone of serni-vertex angle $\;\theta\; $ Find the electric flux through the base of the cone

asked Feb 14, 2014 by yamini.v

1 answer

The current in the primary circuit of a potentiometer is $0.2 A$. The specific resistance and cross-section of the potentiometer wire are $4 \times 10^{-7} ohm $ meter and $8 \times 10^{-7} \: m^2$ respectively. The potential gradient will be equal to:

asked Feb 13, 2014 by thanvigandhi_1

1 answer

If $400ohms $ of resistance is made by adding four $ 100 \: ohm $ resistances of tolerance 5%, then the tolerance of the combination is:

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Time constant of a $RC$ circuit is $2/ln(2) s$. Capacitor is discharged at time $ t = 0$. The ratio of charge on the capacitor at time $t = 2s$ and $t = 6s$ is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

The potential difference across the terminals of the battery (with $2\;ohms$ internal resistance) is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

The current passing through the $ 3\Omega$ resistor is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Under what conditions, can the current passing through the resistance R be increased? r1 and r2 are the internal resistances of the two batteries.

asked Feb 13, 2014 by thanvigandhi_1

1 answer

In a modified YDSE a monochromatic uniform and parallel beam of light of wavelength 6000 A and intensity $\bigg(\large\frac{10}{\pi}\bigg) \large\frac{w}{m^2}$ is incident normally on two circular operates A and B of radii $0.001\;m $ and $0.002\;m$ respectively. A perfectly transparent film of thickness $2000 A^{\circ}$ and refractive index $1.5 $ for wavelength $6000\;A^{\circ}$ is placed in front of aperture A. Calculate the pour (in waters) received at Focal spot F of lens. The lens is symmetrically placed with respect to aperture. Assume $10 \%$ of power received by each aperture goes in original direction and is bought to focal speet.

asked Feb 13, 2014 by meena.p

1 answer

An inductor of inductance $ L = 400\: mH$ and resistors of resistances $R1 = 2\Omega$ and $R2 = 2\Omega$ are connected to a battery of $emf\: 12V$ as shown in the figure. The internal resistance of the battery is negligible. The switch $K$ is closed at $t= 0$. The potential drop across $L$ as a function of time is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Two points $P$ and $Q$ are maintained at the potentials of $10V$ and $-4V$ respectively. The work done in moving $100$ electrons from $P$ to $Q$ is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Two conductors have the same resistance at $0^{\circ} C$ but their temperature coefficients of resistance are $ \alpha 1 \: and \: \alpha 2$. The temperature coefficient for the parallel combination is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Two conductors have the same resistance at $0^{\circ}C$ but their temperature coefficient of resistance are $ \alpha 1\: and \: \alpha 2$. The temperature coefficient for the series combination is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

A beam of light consisting of two wavelength $6500 A^{\circ}$ and $5200 A^{\circ}$ is used to obtain interference fringes in a young's double slit exp. Then what is the distance from central maxima where the bright fringes due to both wavelength coincides? The distance between slits is 2 mm and distance between plane of slits and screen is 120 cm

asked Feb 13, 2014 by meena.p

1 answer

In the circuit shown below, the key K is closed at $ t = 0$. The current through the battery is

asked Feb 13, 2014 by thanvigandhi_1

1 answer

The intensity of an electric field depends on the coordinates x and y as follows $\;\overrightarrow{E}=\large\frac{a\;(x \hat{i} + y \hat{j})}{x^2+y^2}\;$ where a is constants. Find the charge within a sphere of radius R with the centre at the origin

asked Feb 13, 2014 by yamini.v

1 answer

A 4 cm thick layer of water covers 6 cm thick glass slab. A coin is placed at the bottom of slab and is being observed from the air side along the normal to surface. Then the apparent position of coin surface is

asked Feb 13, 2014 by meena.p

1 answer

A $1.37\; M$ aqueous solution of citric acid ($H_3C_6 H_5O_7$; Molecular Weight = $192.1 g/mol$) has a density of $1.10 g/cm^{3}.$ What is the molality and mole fraction of the citric acid?

asked Feb 13, 2014 by sreemathi.v

1 answer

What is the molarity of 0.60N $H_3PO_4$ (a tribasic acid)in the following reaction?$H_3PO_4+2OH^-\rightarrow HPO_4^{2-}+2H_2O$

asked Feb 13, 2014 by sreemathi.v

1 answer

In a YDSE with $D= 1m,d=1mm$ light of wave length $500 \;nm$ is incident at an angle of $0.57^{\circ}$ with respect to axis of symmetry of experimental set up. If centre of symmetry of screen is 0. Then the intensity at point 0 in terms of intensity of central maxima $I_0$ is

asked Feb 13, 2014 by meena.p

1 answer

A charged +Q is uniformly distributed in a spherical volume of radius R . A particle of charge +q and mass m projected with velocity $\;v_{0}\;$ from the surface of the spherical volume to its centre inside a smooth tunnel dug across the sphere . The minimum value of $\;v_{0}\;$ such that it just reaches the centre of the spherical volume is

asked Feb 13, 2014 by yamini.v

1 answer

What is the normality of 0.20M $H_3PO_4$ (a tribasic acid)in the following reaction?$H_3PO_4+2OH^-\rightarrow HPO_4^{2-}+2H_2O$

asked Feb 13, 2014 by sreemathi.v

1 answer

Let C be the capacitance of a capacitor discharging through a resistor R. Suppose t1 is the time taken for the energy stored in the capacitor to reduce to half its initial value and t2 is the time taken for the charge to reduce to one-fourth its initial value. Then the ratio $ \large\frac{t1}{t2}$ will be

asked Feb 13, 2014 by thanvigandhi_1

1 answer

Ask Questions, Get Answers