Nuclear chemistry Questions and Answers

5 pts For 226Rn number of protons 5 pts For 222Rn number of protons th 5 pts For 226Rn number of protons 5 pts For 222Rn number of protons 222 86 45 30 136 5 pts For 226Rn number of protons 30 222 136 45 222Rn number of protons number of neutrons number of neutrons number of neutrons number of neutrons 226 45 140 222 136 number of neutrons number of neutrons and number of electrons and number of electrons gmatill I Due date 20 10 2 and number of electrons and number of electrons Next page Due date 20 and number of electrons and number of electrons

Match the nuclear processes given in List I with the appropriate option s in List II List l List II P a decay 1 n p ratio increases Q B decay 2 n p ratio decreases R Positron decay 3 Proton converts into neutron S 7 ray emission 4 Neutron converts into proton 5 Energy is released The correct option is OP 1 5 Q 2 4 5 R 1 3 5 S5 O P 1 4 Q 1 5 R 2 3 5 S 1 5 OP 2 3 Q2 5 R 3 5 S 1 5 OP 1 5 Q 4 5 R 2 S 1 4 5

82 A sample of 338 when kept at 298 K in a closed vessel shows a decay and B decay to give 226 Pb After t hour the volume of gas collected in the vessel at 1 atm 273K is found to be 89 6 ml Then which of the following is are correct for the nuclear process and the products of the process Mass of Pb obtained in time t hour 103 mg If the temperature is increased by 10 C then the time taken for the same amount of gas to be produced will be less than t hours a particles show more ionisation power than 3 particles Oy radiations undergo no deviation while traveling through electric or magnetic fields

Radioactive decay can be described by the following equation In A In Ao kt where Ao is the original amount of the substance A is the amount of the substance remainin after time t and k is a constant that is characteristic of the substance For the radioactive isotope cesium 129 k is 2 17 x 10 2 hours 1 If the original amount of cesium 129 in a sample is 50 5 mg how much cesium 129 remains after 34 6 hours have passed mg

The failure of classical wave theory to account the distribution of energy in the spectrum of black bod radiation was due to the assumption that radiation energy is a continuous b discrete c a mixture of continuous and discrete d electromagnetic

A photon of 300 nm is absorbed by a gas and then emits two photons one photo has a wavelength 496 nm then the wavelength of second photon in nm is Question Type Single Correct Type 1 959 2 859 3 759

Read the graph given below and calculate the threshold frequency and work function for metal used in photoelectric effect from the graph of KE and frequency of incident radiation 3 8 cv T 1 2 ev KE of photoelectron frequency of incident radiation COF 21 10 34

For the following solution determine whether it is equilibrium and justify your choice If it is not use Le Chatelier s principle to predict and justify the results Would a ppt be expected to form if a solution is prepared from a mixture of 1 0 L of lead II nitrate solution that was 0 00010M was added to 1 0L of 1 4 10 3M in potassium sulfate is added to a solution that is 5 0 10 5M sodium chromate Would you expect a precipitate to form If so Justify

A closed vessel with rigid walls contains 1 2 mol of 23892U and 1 mol of air at 298 K Considering complete decay of 23892U to 20682Pb the ratio of the final pressure to the initial pressure of the system at 298 K is uestion Type Numerical Type

the photon strikes the electron the impact changes its position and velocity both According to the principle of optics the accuracy with which the position of a particle can be ascertained depends on the wavelength of light used i e uncertainty in position is It shows that shorter the wavelength greater is the accuracy in position But a radiation that has a short wavelength is very energetic in nature When a photon of high energy strikes the electron the impact causes a change in the velocity and

In electric deflection 1 a rays 3 D ray field which have maximum angle of Assume all have same velocity 2 H rays 4 All have equal highest

Which one of the following statements regarding paracetamol overdose is false O O O O O Headache The toxic metabolite in paracetamol overdose is NAPQI O Kidney injury by metabolite Patients getting anticonvulsant

7 92 U235 nucleus absorbs a neutron and disintegrates into 54 Xe139 38 Sr94 and x What will be the product x 1 3 neutrons 2 2 neutrons 3 2 a particles 4 2 B particles

3 2 particles 8 The half life of C 14 is 5600 years A sample of freshly cut wood from a tree contains 10 mg of C 14 The amount left in the sample after 50000 years is a x 100 The value of a x x 100 is 11 2 2 4 4 IS 3 3

At very low pressure real gases show minimum deviation from ideal behaviour The compressibility factor for an ideal gas is zero At Boyle temperature real gas behave as ideal gas in high pressure region Real gas show maximum deviation at high pressure and low temperature

When light of wavelength 248 nm falls on a metal of threshold energy 3 0 eV the de Broglie wavelength of emitted electrons is Round off to the Nearest Integer Use 3 1 73 h 6 63 x 10 34 Js m 9 1 x 10 31 kg c 3 0 108 ms me 1eV 1 6 10 1 J

4 Thiosulphate ions upon reaction with AgNO give white precipitate which gradually changes to black upon hydrolysis the sum of the oxidation state of sulphur in the products obtained after hydrolysis is

9 Energy required to excite the electron in a hydrogen atom from 2nd to 3rd orbit is 1 3 63 10 1 J 3 3 00 x 10 19 J NCERT Pg 48 2 2 18 10 18 J 4 5 45 10 19 J 0 de Broglie wavelength of 20 g ball moving with a velocity of 50 ms is NCERT Pg 50 1 6 626 x 10 7 m 1 2 6 626 x 10 34 m 1 m l L

4 The mean lives of a radioactive substance are 1620 year and 405 year for alpha emission and beta emission respectively what the time during which th of a sample will decay if it is decaying both by alpha emission and beta emission simultaneously W A 470 45 year B 449 24 year C 269 57 year D 345 56 year O A B O C D

One of the hazards of nuclear explosion is the generation of Sr9 0 and its subsequent incorporation in Expo bones This nucleide has a half life of 30 year Suppose one microgram was absorbed by a new born child how much Sr will remain in his bones after 20 years Take log 1 6 2 log 2 3

16 Low mass nuclei combine to form a heavier more stable nucleus Choose Rem Daughter Alpha Fusion Parent Positron Fission otons and two neutrons bound together e charge and same mass as an electron

IS384 Hg the rate The reaction given below rate constant for disappearance of A is 7 48 x 10 3 sec Calculate the time required for the total pressure in a system containing A at an initial pressure of 0 1 atm to rise to 36 0 145 atm and also find the total pressure after 100 sec KD K k kB kc 2 Ad g 4B g C g a b Aia d t 1 Im A o A E optical rotation of reaction 37

Single 1 Bombardment of aluminium of a particle leads to its artificial disintegration in two ways i and ii as shown below Product X Y and Z respectively are 14Si30 X i 134127 1 Proton neutron positron 2 Neutron positron proton 3 Proton positron neutron 4 Positron proton neutron 15 P30 Y Si 0 Z 14

21 Nuclides produced by the decay of the parent nuclides Choose Rem Daughter Alpha Fusion Parent Positron Fission re nuclear radiation exposure re the dose of any type of ionizing radiation that factors iation has on human tissue

18 Particle with a positive charge and same mass as an electron Choose Rem Daughter Alpha Fusion Parent Positron Fission ich decay series ucleus splits into more stable nuclei of intermediate

JEE MAIN 22nd July Second shift Memory Based Paper Discussion Chemist sotopes of hydrogen which emits low energy 3 particle with half life value greater than 12 years is 2 4 Tritium and Deuterium Deuterium uum Protium

7 When a hydrogen sample in ground state i bombarded then what potential is required to accelerate electron so that first Paschen line i emitted 1 2 55 V 3 12 09 V 2 0 65 V 4 12 75 V

The radius of the second Bohr orbit for hydrogen atom is in Planck s constant h 6 6262 10 34 Js mass of electron 9 1091 x 10 1 kg charge of electron e 1 60210 10 1 C permittivity of vacuum the radius of first Bohr orbit is 0 6 E 8 854185 x 10 12 kg 1 m 3 A

Consider a beam of neutrons where every neutron in the beam has kinetic energy E 0 05eV Take the half life and the rest energy of a neutron to be T1 2 900 In2 sec and mc 810MeV respectively Find the fraction of the number of neutrons which will decay before the beam travels a distance of d 10m If your answer is x x 10 then fill value of x

66 One of the hazards of nuclear explosion is the generation of Sr90 and Subsequent incorporation in bones This nucleide has half life of 28 1 Suppose one microgram was absorbed by a new born child how much Sr remain in his bones after 20 yr 1995 2M

4 they The cations having same size and charge one having n 1 d ns configuration possess more polarising power because is 1 It is d bolock element 3 It has effective shielding of d electrons 2 It has inert gas configuration 4 it has more Zeff due to poor shielding of d electrons MOLECULAR STRUCTURE

3 The correct option for free expansion of an ideal gas under adiabatic condition is 1 q 0 AT 0 and w 0 2 q 0 AT 0 and w 0 3 q 0 AT 0 and w 0 4 q 0 AT 0 and w 0

b Frequency of this light is 5 x 10 4 S c Energy of photon is approximately 2 07 eV d Both b and c 4 Photon having wavelength 310 nm is used to break bond of A molecule having bond energy 288 kJ m then the percentage of energy of photon converted to is 1 eV 96 kJ mol a 25 b 50 T1 c 75 d 80

a 34 c 122 4 eV d 2 The de broglie wavelength of an electron moving circular orbit is The minimum radius of the orbit is given by a 2 4 3 light gives off yellow light that E a TC b 2 C d

Which of the following is incorrect statement about the Bragg s equation n 2d sine 1 n represents order of reflection 2 represents wavelength of UV rays used 3 0 represents angle of incidence 4 d represents distance between two parallel planes

Calculate the wavelength of light required to break the bond between two bromine atom in bromine molecule The Br Br bond energy is 93 kJ mol Take N 6x 1023 h 6 6 10 34 J s A 1 27 x 106m B 1 26 10 m C 1 8 10 20 m D 1 9 10 13 m The radius ratio of two orbits of Li2 is 1 16 What is the ratio of frequency of revolution of electron in these orbits

The uncertainty in the momentum is four times the uncertainty in position of a particle The minimum uncertainty in the velocity of the particle is I B 2m T D 4m T

1 Mole of an ideal gas initially at 400 K and 10 atm is first expanded at constant pressure till the volume is doubled Then the gas is made to undergo an isochoric process in which its temperature is found to decrease In the last final step gas compressed reversible and adiabatically to initial state Determine the net work involved in this cyclic process in terms of R Given Cv for gas 1 5 R 4 1 3 0 63 If W 2R xz report your answer as z

What is the ratio of the time period of revolution of electron He ion sample in the orbit where the path length is three time the de broglies wavelength to the time period of revolution in the ground state 1 27 1 2 1 27 3 9 8 4 8 9

53 pl3 Q a t 1000 hrs QR b t 2 10 min Number of nuclei of Q and R respectively after 1000 hr if we start with 2 mo N 6 10 A 6 1023 6 10 3 B 6 1022 6 10 3 C 2 1020 6 1023 D 1020 6 10 3

Maxwell said that when electron accelerate they emits electromagnetic radiation Now we can say in reality that electron is not accelerate when it moves circular orbit It accelerate that time when it emits electromagnetic radiation

A real gas at a very high pressure occupies more volume than that of an ideal gas under identical conditions A B C less volume than that of an ideal gas under identical conditions Same volume than that of an ideal gas under identical conditions

4 n a e p g 600X10 4 n c 54 The frequency of yellow light having wavelength 600 nm is 54 a g 15 0 x 10 4 Hz 2 2 5 107 Hz 1 5 0 3 5 0 x 107 Hz 4 2 5 x 10 4 Hz 3 5 0

35 Photoelectric effect is the phenomenon in which a photons come out of a metal when it is hit by a beam of electrons b photons come out of the nucleus of an atom under the action of an electric field c electrons come out of a metal with a constant velocity which depends on the frequency and intensity of incident light wave 145 out of a metal with different electrons come velocities not greater than a certain value which depends only on the frequency of the incident light wave and not on its intensity increasing order lowest first for the values of e m 6

Nitrogen occurs in nature in the form of two isotopes with atomic mass 14 u and 15 u respectively If the average atomic mass of nitrogen is 14 0067 u what is the abundance of the N 15 isotopes upto 2 decimals A 0 97 B C D 0 67 0 10 0 50

Q 14 O 10 4 1 O 5 10 4 00 19 The rate constant of a first order reaction at 27 C is 10 min The temperature coefficient of this reaction is 2 What is the rate constant in min at 17 C for this reaction 000

2 d TB 0 5eV 57 The frequency v of certain line of the Lyman series the atomic spectrum of hydrogen satisfies the follow conditions 1 It is the sum of the frequencies of another Lyman ii It is the sum of the frequencies of a certain line and a Balmer line Lyman line and a Paschen line

At a certain temperature the half life periods for the catalytic decomposition of NH were found to be as follows Pressue mm Hg 50 100 200 Half life period hrs 3 52 1 76 0 88 What will be the pressure when the half life perriod is 1 5 hours

are as follows What is order of reaction Initial concentration 350 540 158 425 275 941 11 2 1 0 5 2 1 5 3 2 5 lire period and initial concentration for a reaction 7 4 2 0 5 32 675 25 12 5 FR F t 2 1 0 5 2 1 5 3 2 5 4 2 a E BERA hell and fetit 350 540 1 58 425 275 941 auform for for ade

The beta activity of 1g of carbon made from green wood is 15 3 counts per minute If the activity of 1 g of carbon derived from the wood of an Egyption mummy case is 9 4 counts per minute the same conditions how old is the wood of the mummy case Half Life of carbon 5770 yr