235 questions from a source that prints this span of years rather than the year of each question. Each opens with its answer and explanation.
ABC26PH0631 · For an electron whose x-positional uncertainity is 1 10-10 m, the uncertainity in x-component of the velocity in ms-1 will be of the order… · Atomic Structure – General
ABC26PH0632 · Identify the correct statement regarding Einstein's photoelectic effect · Atomic Structure – General
ABC26PH0633 · Ionisation energy of hydrogen atom is ground state is 13.6 eV. The energy released (in eV) for third member of Balmer series is · Atomic Structure – General
ABC26PH0634 · The electron of a hydrogen atom is in its n^ th Bohr orbit having de Broglie wavelength of 13.4 . The value of n is ____ (rounded up to the… · Atomic Structure – General
ABC26PH0635 · The ionization energy of hydrogen atom is 13.6 eV and the first ionization energy of sodium atom is 5.1 eV. The effective nuclear charge… · Atomic Structure – General
ABC26PH0636 · Given that the radius of the first Bohr orbit of hydrogen atom is 53 pm , the radius of its third Bohr orbit is ____ pm. (Round off to the… · Atomic Structure – General
ABC26PH0637 · The longest wavelength of light absorbed by a hydrogen - like atoms is 2.48 nm. The nuclear charge (Z) of the atom is ____ (Round off to… · Atomic Structure – General
ABC26PH0638 · Two sets of quantum numbers with the same number of radial nodes are · Atomic Structure – General
ABC26PH0639 · The ratio of the 2 p 1 s transition energy in He+to that in the H atom is closest to · Atomic Structure – General
ABC26PH0640 · The equilibrium constant for the reaction Fe3 O4(s)+CO(g) 3 FeO(s)+CO2(g) at 600 C is 1.00. If a mixture initially consisting of 1 mole of… · Chemical Equilibrium – General
ABC26PH0641 · The temperature ( T ) dependence of the equilibrium constant ( K ) of a chemical reaction is correctly described by the following statement: · Chemical Equilibrium – General
ABC26PH0642 · The reaction N2+3 H2 2 NH3 is carried out at 300 K by mixing N2 and H2. The standard free energy of formation of NH3 is -16.4 kJ / mol… · Chemical Equilibrium – General
ABC26PH0643 · Consider the reaction. CH4(g)+2 O2(g) CO2(g)+2 H2 O() Delta Ho=-606.9 kJ mol-1 Assuming ideal behaviour, calculate Delta U when 1 mol of… · Chemical Equilibrium – General
ABC26PH0644 · Equilibrium constant for a reaction doubles as the temperature is increased from 300 K to 600 K. Calculate the standard reaction enthalpy… · Chemical Equilibrium – General
ABC26PH0645 · For the following equilibrium at 300 C. N2 O4(g) 2 NO2(g) Calculate Kp when N2 O2 is 30 \% dissociated and the total pressure is 2 bar. · Chemical Equilibrium – General
ABC26PH0646 · For the equilibrium N2+3 H2 2 NH3, the equilibrium constant, KP is expressed as · Chemical Equilibrium – General
ABC26PH0647 · For the reaction, 2 SO2+O2 2 SO3, the equilibrium constant KP=5.0 at 207 C. If the partial pressures of SO2, O2 and SO3 are 1.0 10-3, 0.20… · Chemical Equilibrium – General
ABC26PH0648 · A 10 L flask containing 10.8 g of N2 O5 is heated to 373 K , which leads to its decomposition according to the equation 2 N2 O5(g) 4… · Chemical Equilibrium – General
ABC26PH0649 · A vessel contains a mixture of H2 and N2 gas. The density of this gas mixture is 0.2 g L-1 at 300 K and 1 atm . Assuming that both the… · Chemical Equilibrium – General
ABC26PH0650 · Consider the reaction CO(g)+1/2 O2(g) CO2(g). The value of Delta U for the reaction at 300 K is -281.8 kJ mol-1. The value of Delta H at… · Chemical Equilibrium – General
ABC26PH0651 · A dilute solution prepared by dissolving a nonvolatile solute in one liter water shows a depression in freezing point of 0.186 K . This… · Complex Reactions
ABC26PH0652 · A salt mixture (1.0 g) contains 25 wt\% of MgSO4 and 75 wt\% of M2SO4. Aqueous solution of this salt mixture on treating with excess BaCl2… · Rate Laws Order
ABC26PH0653 · For the reaction, Q+R k-1k1 X k2 P k1=2.5 105 L mol-1 s-1, k-1=1.0 104 s-1 and k2=10 s-1. Under steady state approximation, the rate… · Chemical Kinetics – General
ABC26PH0654 · The intensity of a monochromatic visible light is reduced by 90 \% due to absorption on passing through a 5.0 mM solution of a compound. If… · Chemical Kinetics – General
ABC26PH0655 · Elemental analysis of an organic compound containing C, H and O gives percentage composition: C: 39.9\% and H: 6.7\%. If the molecular… · Chemical Kinetics – General
ABC26PH0656 · In 200 g of water, 0.01 mole of NaCl and 0.02 mole of sucrose are dissolved. Assuming solution to be ideal, the depression in freezing… · Rate Laws Order
ABC26PH0657 · The half-life of the chemical reaction, A Product, for initial reactant concentrations of 0.1 and 0.4 mol L-1 are 200 and 50 s… · Rate Laws Order
ABC26PH0658 · The turnover frequency (TOF) for the catalytic reaction, A(1 mol) [ 5 hours ] Catalyst (0.01 mol) B with 90\% yield of the product is ____… · Chemical Kinetics – General
ABC26PH0659 · (being typed) · Chemical Kinetics – General
ABC26PH0660 · The vapour pressure of benzene is 5333 Pa at 7.6 C and 53330 Pa at 60.6 C. Calculate the heat of vapourization of benzene and the normal… · Chemical Kinetics – General
ABC26PH0661 · A mixture of C3 H8 and oxygen in 1 L closed vessel has an internal pressure of 4 atm at 100 C. When the mixture is ignited, the reaction… · Chemical Kinetics – General
ABC26PH0662 · An aqueous solution containing 1 g L-1 of a polymer exerts osmotic pressure of 4 torr at 300 K . Given R=0.082 L atm, the molar mass (g… · Chemical Kinetics – General
ABC26PH0663 · The most viscous liquid is · Rate Laws Order
ABC26PH0664 · Addition of 1.0 g of a compound to 10 g of water increases the boiling point by 0.3 C. The amount of compound needed to prepare a 500 ml or… · Chemical Kinetics – General
ABC26PH0665 · The kinetics of the reaction 2 N2 O5 4 NO2+O2 in liquid bromine medium was measured independently for three different initial concentration… · Rate Laws Order
ABC26PH0666 · A 2.5 10-4 M solution of a complex exhibits an absorption maximum at 625 nm with an absorbance of 0.90 when measured in a cuvette with a… · Chemical Kinetics – General
ABC26PH0667 · For a reaction, the rate constant at 25°C is doubled when the temperature is raised to 45°C. The activation energy (in kJ\,mol-1) of the… · Arrhenius Activation
ABC26PH0668 · An aqueous solution of hemoglobin has a molar absorptivity value of 18,600\,L\,mol-1\,cm-1 for an absorbance value of 0.1 at 540 nm (Given… · Chemical Kinetics – General
ABC26PH0669 · For the reaction: 2 NO+2 H2 700 C N2+2 H2 O (i) Write the expression for the rate of the reaction in terms of the change in concentrations… · Rate Laws Order
ABC26PH0670 · For a particular reaction at constant temperature, a plot of inverse of reactant concentration (1/([A]) ) versus time is a straight line… · Chemical Kinetics – General
ABC26PH0671 · A solution containing 250 ppm of CuSO4 5 H2 O (formula weight =250 ) has an absorbance of 0.1 measured in 1 cm cell at 600 nm . Calculate… · Chemical Kinetics – General
ABC26PH0672 · The half-life of any zero-order reaction is: · Rate Laws Order
ABC26PH0673 · The percent transmittance of a solution having absorbance (optical density) 1.0 is · Chemical Kinetics – General
ABC26PH0674 · The mechanism of isomerization of cyclobutene (CB) to 1, 3-butadiene (BD) is as follows. arrayl CB + CB k1 CB* + CB \\ CB* + CB k-1 CB + CB… · Rate Laws Order
ABC26PH0675 · (a) For the reaction R P, the plot of [R] versus time (t) gives a straight line with a negative slope. The half life for the reaction is 3… · Chemical Kinetics – General
ABC26PH0676 · For the reaction, H2(g) + Br2(g) 2HBr(g) the following mechanism has been proposed. arrayl Initiation: Br2 + M ki Br + Br + M \\… · Steady State Approximation
ABC26PH0677 · For the formation of B from A , heat liberated is 20 kJ mol-1. If the activation energy for the reaction B A is 100 kJ mol-1, then the… · Arrhenius Activation
ABC26PH0678 · For the reaction A + B Z, the concentration of Z at time t is given by [Z] = [A]t=0(1-e-kt) + [Z]t=0, where k is the rate constant. The… · Rate Laws Order
ABC26PH0679 · The following initial rate data were obtained for the reaction 2NO(g) + O2(g) 2NO2(g) (i) What is the rate law for this reaction? (ii) One… · Steady State Approximation
ABC26PH0680 · For a zero order reaction, units of the rate constant is expressed as · Rate Laws Order