Nuclear Chemistry Test 1

Total Questions:50 Total Time: 75 Min

Remaining:

 

Questions 1 of 50

Question:The first artificial disintegration of an atomic nucleus was achieved by

Answers Choices:

Geiger

Wilson

Madame curie

Rutherford

Soddy

Questions 2 of 50

Question:Artificial elements have been prepared by bombardment reactions in high energy accelerators. What is the mass number of the element X produced in the following nuclear reaction \(_{95}^{249}Cf+_7^{15}N{\to_{105}}X+4_0^1n\)

Answers Choices:

261

264

260

257

Questions 3 of 50

Question:The proper rays for radiocarbon dating are

Answers Choices:

UV-rays

IR-rays

Cosmic rays

X-rays

Questions 4 of 50

Question:\(_1{H^2}+{\,_1}{H^2}\to{\,_2}H{e^3}+{\,_0}{n^1}\). Above nuclear reaction is called

Answers Choices:

Nuclear fission

Nuclear fusion

Artificial transmutation

Spontaneous disintegration

Questions 5 of 50

Question:Large energy released in an atomic bomb explosion is mainly due to

Answers Choices:

Products having a lesser mass than initial substance

Conversion of heavier to lighter atoms

Release of neutrons

Release of electrons

Questions 6 of 50

Question:The reaction \(_1{H^2}+{\,_1}{H^3}\to{\,_2}H{e^4}+{\,_0}{n^1}+\)energy represents

Answers Choices:

Nuclear fission

Nuclear fusion

Artificial disintegration

Transmutation of element

Questions 7 of 50

Question:\(C-14\) is used in carbon dating of dead objects because

Answers Choices:

Its half-life is \({10^3}\) years

Its half-life is \({10^4}\) years

It is found in nature abundantly and in definite ratio

It is found in dead animals abundantly

Questions 8 of 50

Question:A radioactive element resembling iodine in properties is

Answers Choices:

Astatine

Lead

Radium

Thorium

Questions 9 of 50

Question:In a nuclear reactor, chain reaction is controlled by introducing

Answers Choices:

Iron rod

Cadmium rod

Graphite rod

Platinum rod

Questions 10 of 50

Question:In atomic reactors, graphite is used as a

Answers Choices:

Lubricant

Moderator to slow down neutrons

Fuel

Liner of the reactor

Questions 11 of 50

Question:Radioactive disintegration differs from a chemical change in being

Answers Choices:

An exothermic change

A spontaneous process

A nuclear process

A unimolecular first order reaction

Questions 12 of 50

Question:\(_{92}^{238}U\) emits 8 \(\alpha \)-particles and 6 \(\beta \)-particles. The neutron/proton ratio in the product nucleus is

Answers Choices:

60/41

61/40

62/41

61/42

Questions 13 of 50

Question:\(_{13}^{27}Al\) is a stable isotope. \(_{13}^{29}Al\) is expected to disintegrate by

Answers Choices:

\(\alpha\)-emission

\(\beta\)-emission

Positron emission

Proton emission

Questions 14 of 50

Question:An isotope \(_Y{A^X}\) undergoes a series of \(m\) alpha and \(n\) beta disintegration to form a stable isotope \(_{Y-10}{B^{X-32}}\). The values of \(m\) and \(n\) are respectively

Answers Choices:

6 and 8

8 and 10

5 and 8

8 and 6

Questions 15 of 50

Question:What is the symbol for the nucleus remaining after \(_{20}C{a^{42}}\) undergoes \(\beta\)-emission

Answers Choices:

\(_{21}C{a^{42}}\)

\(_{20}S{c^{42}}\)

\(_{21}S{c^{42}}\)

\(_{21}S{c^{41}}\)

Questions 16 of 50

Question:When a radioactive nucleus emits an \(\alpha\)-particle, the mass of the atom

Answers Choices:

Increases and its at. number decreases

Decreases and its at. number decreases

Decreases and its at. number increases

Remains same and its at. number decreases

Questions 17 of 50

Question:If the quantity of a radioactive element is doubled, then its rate of disintegration per unit time will be

Answers Choices:

Unchanged

Reduced to half

Increased by \(\sqrt2\)times

Doubled

Questions 18 of 50

Question:The number of\(\alpha \) and \(\beta \) -particles emitted during the transformation of \(_{90}T{h^{232}}\) to \(_{82}{P^{208}}\) are respectively

Answers Choices:

4, 2

2, 2

8, 6

6, 4

Questions 19 of 50

Question:The disintegration constant of radium with half-life 1600 years is

Answers Choices:

\(2.12\times{10^{-4}}yea{r^{-1}}\)

\(4.33\times{10^{-4}}yea{r^{-1}}\)

\(3.26\times{10^{-3}}yea{r^{-1}}\)

\(4.33\times{10^{-12}}yea{r^{-1}}\)

Questions 20 of 50

Question:The number of \(\alpha\) and \(\beta-\)particles emitted in the nuclear reaction \(_{92}{U^{238}}{\to_{90}}T{h^{234}}{\to_{91}}P{a^{234}}\)are respectively

Answers Choices:

1 and 1

1 and 2

2 and 1

2 and 2

Questions 21 of 50

Question:Radioactive isotopes that have an excessive neutron/proton ratio generally exhibit

Answers Choices:

\({e^-}\) emission

\(_2H{e^4}\) emission

\({e^+}\) emission

K -electron capture

Questions 22 of 50

Question:Atomic weights of carbon, nitrogen and oxygen are 12, 14 and 16 respectively. An atom of atomic weight 14 and nuclear charge + 6 is an isotope of

Answers Choices:

Oxygen

Carbon

Nitrogen

None of these

Questions 23 of 50

Question:Which of the following is an isotonic pair

Answers Choices:

\(_{19}^{40}K,\,_{20}^{40}Ca\)

\(_{19}^{39}K,\,_{20}^{40}Ca\)

\(_{18}^{33}Ar,\,_{\,18}^{40}Ar\)

\(_{18}^{40}Ar,\,_{\,20}^{40}Ca\)

Questions 24 of 50

Question:\(_6{C^{11}}\) and \(_5{B^{11}}\) are referred as

Answers Choices:

Nuclear isomers

Isobars

Isotopes

Fission products

Questions 25 of 50

Question:Two nuclei which are not identical but have the same number of nucleons represent

Answers Choices:

Isotopes

Isobars

Isotones

None of the three

Questions 26 of 50

Question:The \(\beta\)-decay of \(_{11}N{a^{24}}\) produces an isotope of

Answers Choices:

Mg

Na

Al

Ne

Questions 27 of 50

Question:On bombarding \(_7{N^{14}}\) with \(\alpha\)-particles, the nuclei of the product formed after the release of a proton will be or In nuclear reaction \(_7{N^{14}}+{\,_2}H{e^4}{\to_Z}{X^A}{+_1}{H^1}\), the term \(_Z{X^A}\) represents

Answers Choices:

\(_8{O^{17}}\)

\(_9{F^{18}}\)

\(_9{F^{17}}\)

\(_8{O^{18}}\)

Questions 28 of 50

Question:Nuclear energy is based on the conversion of

Answers Choices:

Protons into neutrons

Mass into energy

Neutrons into protons

Uranium into radium

Questions 29 of 50

Question:In the nuclear reaction \(_{12}M{g^{24}}{+_2}H{e^4}{=_0}{n^1}+?\) The product nucleus is

Answers Choices:

\(_{13}A{l^{27}}\)

\(_{14}S{i^{27}}\)

\(_{13}A{l^{28}}\)

\(_{12}M{g^{25}}\)

Questions 30 of 50

Question:\(_6{C^{14}}\) is formed from \(_7{N^{14}}\) in the upper atmosphere by the action of the fundamental particle

Answers Choices:

Positron

Neutron

Electron

Proton

Questions 31 of 50

Question:In terms of energy 1 a. m.u. is equal to

Answers Choices:

100 J

931.1 MeV

931.1 kcal

\({10^7}\)erg

Questions 32 of 50

Question:Positron is

Answers Choices:

Electron with +ve charge

A helium nucleus

A nucleus with two protons

A nucleus with one neutron and one proton

Questions 33 of 50

Question:Which of the following particle is emitted in the reaction \(_{13}A{l^{27}}{+_2}H{e^4}{\to_{14}}{P^{30}}+.....\)

Answers Choices:

\(_0{n^1}\)

\(_{-1}{e^0}\)

\(_1{H^1}\)

\(_1{H^2}\)

Questions 34 of 50

Question:Which of the following sub-atomic particles is not present in an atom

Answers Choices:

Neutron

Proton

Electron

Positron

Questions 35 of 50

Question:Which statement is incorrect

Answers Choices:

\(\alpha\)-rays have more penetrating power than \(\beta\)-rays

\(\alpha\)-rays have less penetrating power than \(\gamma\)-rays

\(\beta\)-rays have less penetrating power than \(\gamma\)-rays

\(\beta\)-rays have more penetrating power than \(\alpha\)-rays

Questions 36 of 50

Question:The velocity of \(\alpha\)-rays is approximately

Answers Choices:

Equal to that of the velocity of light

1/10 of the velocity of light

10 times more than the velocity of light

Uncomparable to the velocity of light

Questions 37 of 50

Question:Choose the element which is not radioactive

Answers Choices:

\(Cm\)

\(No\)

\(Mo\)

\(Md\)

Questions 38 of 50

Question:A magnet will cause the greatest deflection of

Answers Choices:

\(\gamma\)-rays

\(\beta\)-rays

\(\alpha\)-rays

Neutrons

Questions 39 of 50

Question:The charge on gamma rays is

Answers Choices:

Zero

1

1

2

Questions 40 of 50

Question:A nuclear reaction is accompanied by loss of mass equivalent to \(0.01864\;amu\). Energy liberated is

Answers Choices:

\(931\;MeV\)

\(186.6\;MeV\)

\(17.36\;MeV\)

\(460\;MeV\)

Questions 41 of 50

Question:\(10gm\) of a radioactive substance is reduced to \(1.25gm\) after 15 days. Its \(1kg\) mass will reduce (in how many days) to \(500gm\) in

Answers Choices:

500 days

125 days

25 days

5 days

Questions 42 of 50

Question:A radioactive isotope having a half-life of 3 days was received after 12 days. It was found that there were 3 gm of the isotope in the container. The initial weight of the isotope when packed was

Answers Choices:

12 gm

24 gm

36 gm

48 gm

Questions 43 of 50

Question:What is the value of decay constant of a compound having half-life time \({T_{1/2}}=2.95\) days

Answers Choices:

\(2.7\times{10^{-5}}{s^{-1}}\)

\(2.7\times{10^6}{s^{-1}}\)

\(2.7\times{10^{-6}}{s^{-1}}\)

\(3\times{10^5}{s^{-1}}\)

Questions 44 of 50

Question:What kind of radioactive decay does not lead to the formation of a daughter nucleus that is an isobar of the parent nucleus

Answers Choices:

\(\alpha \) -Particle

\(\beta \) - Particle

Positron

Electron capture

Questions 45 of 50

Question:For a radioactive substance with half-life period 500 years, the time for complete decay of 100 milligram of it would be

Answers Choices:

1000 years

\(100\times500\) years

500 years

Infinite time

Questions 46 of 50

Question:A substance of which one gram is taken, after half-life time what fraction of it is left ?

Answers Choices:

\(\frac{1}{4}\)

\(\frac{1}{8}\)

\(\frac{1}{2}\)

\(\frac{1}{{32}}\)

Questions 47 of 50

Question:Given that a radioactive species decays according to exponential law \(N={N_0}{e^{-\lambdat}}\). The half-life of the species is

Answers Choices:

\(\lambda\)

\(No\)

\(\lambda/\ln2\)

\(\ln2/\lambda\)

Questions 48 of 50

Question:Half-life of a radioactive disintegration (A \(\to\)B) having rate constant \(231\,{\sec^{-1}}\) is

Answers Choices:

\(3.0\times{10^{-2}}\) sec

\(3.0\times{10^{-3}}\) sec

\(3.3\times{10^{-2}}\) sec

\(3.3\times{10^{-3}}\) sec

Questions 49 of 50

Question:A radioactive isotope decays at such a rate that after 192 minutes only \(1/16\) of the original amount remains. The half-life of the radioactive isotope is

Answers Choices:

32 min

48 min

12 min

24 min

Questions 50 of 50

Question:Rate constant for a reaction is \(\lambda\). Average life is representative by

Answers Choices:

\(1/\lambda\)

\({\rm{In}}2/\lambda\)

\(\frac{\lambda}{{\sqrt2}}\)

\(\frac{{0.693}}{\lambda}\)