Subatomic particles, atomic models, nucleus

31 questions on Subatomic particles, atomic models, nucleus from the Atomic Structure chapter: 7 NEET level, 12 JEE Main, 12 JEE Advanced. Each one opens with its answer and solution.

• In the gold foil experiment, a very small fraction of the alpha particles bounced back through large angles. Which conclusion was drawn mainly from this observa... NEET level
• The number of neutrons in the nucleus of ^235_92U is NEET level
• ^14_6C and ^15_7N are examples of NEET level
• Which of the following statements about cathode rays is correct? NEET level
• The numbers of electrons, protons and neutrons in ^27_13Al^3+ are respectively NEET level
• A species has 17 protons, 18 neutrons and 18 electrons. It is represented as NEET level
• Millikan's oil drop experiment was used to determine NEET level
• Nuclear radius follows R = R_0 A^1/3. The ratio of the radius of a nucleus of mass number 125 to that of mass number 8 is JEE Main level
• The sum of the number of neutrons and the number of electrons in ^56_26Fe^3+ is JEE Main level
• An alpha particle of kinetic energy K is fired head-on at a fixed gold nucleus and momentarily stops at a distance d_0 from it. A proton of the same kinetic ene... JEE Main level
• The ratio of the radius of the third Bohr orbit of He+ to the radius of the first Bohr orbit of hydrogen is JEE Main level
• In the Bohr model, which pair of hydrogen-like species and levels has the same total electron energy? JEE Main level
• The nucleus of ^4_2He has mass 4.00151 u. Take proton mass 1.00728 u, neutron mass 1.00866 u and 1 u=931.5 MeV/c^2. The binding energy per nucleon is closest to JEE Main level
• Using a_0=0.529 AA, find the radius of the third Bohr orbit of Be^3+ in angstrom, to two decimals. JEE Main level
• The speed of the electron in the first Bohr orbit of hydrogen is 2.18x10^6 m s^-1 and in general v = 2.18x10^6 Z/n m s^-1. Find the speed of the electron in the... JEE Main level
• Take the nuclear radius as R=1.2x10^-15A^1/3 m and the mass of a nucleon as 1.67x10^-27 kg. Find the density of a nucleus of mass number 64 in units of 10^17 kg... JEE Main level
• Which of the following conclusions follow from the alpha-particle scattering experiment on thin gold foil? (Select all that apply.) JEE Main level
• Select the correct statements. JEE Main level
• Which statements about cathode rays are correct? JEE Main level
• An alpha particle of kinetic energy 7.7 MeV is fired head-on at a gold nucleus (Z=79, A=197). Take e^2/(4piepsilon_0)=1.44 MeV fm and nuclear radius R=1.2A^1/3 ... JEE Advanced level
• The number of neutrons in 7.0 g of ^14_6C is closest to (take molar mass 14 g mol^-1 and N_A=6.022x10^23 mol^-1) JEE Advanced level
• In Rutherford scattering the number of alpha particles detected per unit solid angle at scattering angle theta is proportional to 1/sin^4(theta/2) for a fixed b... JEE Advanced level
• Atomic masses: ^1_1H = 1.007825 u, ^2_1H = 2.014102 u, neutron = 1.008665 u; 1 u=931.5 MeV/c^2. The binding energy per nucleon of the deuteron is closest to JEE Advanced level
• An alpha particle of mass 6.64x10^-27 kg moving at 1.6x10^7 m s^-1 approaches a stationary gold nucleus (Z=79) head-on. Treat the nucleus as fixed. Use 1/(4piep... JEE Advanced level
• In the second Bohr orbit of He+, find the time for one revolution of the electron in units of 10^-16 s, to two decimals. Use r_n=0.529x10^-10 n^2/Z m and v=2.18... JEE Advanced level
• Take the radius of an aluminium-27 nucleus as R=1.2x10^-15A^1/3 m and the radius of the atom as 1.5x10^-10 m. The fraction of the atomic volume occupied by the ... JEE Advanced level
• Atomic masses: ^1_1H=1.007825 u, neutron =1.008665 u, ^16_8O=15.994915 u; 1 u=931.5 MeV/c^2. Find the binding energy per nucleon of ^16_8O in MeV, to one decima... JEE Advanced level
• Compare the electron in the n=2 orbit of He+ with the electron in the n=1 orbit of H according to the Bohr model. Select all correct statements. JEE Advanced level
• For the electron of Li^2+ in its ground state (Bohr model, use 13.6 eV for hydrogen), select the correct statements. JEE Advanced level
• A fixed target nucleus is approached head-on by various projectiles. The distance of closest approach is d = k Z_1 Z_2 e^2/K. Which statements are correct? JEE Advanced level
• Consider the species ^127_53I^-. Select all correct statements. JEE Advanced level