Nuclear Chemistry Test 2

Total Questions:50 Total Time: 75 Min



Questions 1 of 50

Question:Radioactive carbon dating was discovered by

Answers Choices:

W.F. Libby

G.N. Lewis

J. Willard Gibbs

W. Nernst

Questions 2 of 50

Question:The nuclear reaction \(_{29}^{63}Cu+_2^4He\to_{17}^{37}Cl+14_1^1H+16_0^1n\) is referred to as

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Spallation reaction

Fusion reaction

Fission reaction

Chain reaction

Questions 3 of 50

Question:Which of the following is used as a moderator in a nuclear reactor

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Questions 4 of 50

Question:The fuel of atomic pile is

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Questions 5 of 50

Question:Carbon-14 dating method is based on the fact that

Answers Choices:

Carbon-14 fraction is the same in all objects

Carbon-14 is highly insoluble

Ratio of carbon-14 and carbon-12 is constant

All of these

Questions 6 of 50

Question:Half-life period of a radioactive element is 10.6 yrs. How much time will it take in its 99% decomposition

Answers Choices:

7046 yrs

7.046 yrs

704.6 yrs

70.4 yrs

Questions 7 of 50

Question:For artificial transmutation of nuclei, the most effective one is

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Helium nuclei


Questions 8 of 50

Question:Which of the following cannot be accelerated

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Questions 9 of 50

Question:The modern basis of atomic weight is

Answers Choices:

Isotope \({H^1}=1.000\)

Oxygen = 16.000

Isotope \({O^{16}}=16.000\)

Isotope \({C^{12}}=12.000\)

Questions 10 of 50

Question:Which radioactive carbon has been helpful in understanding the mechanism of photosynthesis in plants

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Questions 11 of 50

Question:The element with atomic number 84 and mass number 218 change to other element with atomic number 84 and mass number 214. The number of \(\alpha\) and \(\beta\)-particles emitted are respectively

Answers Choices:

1, 3

1, 4

1, 2

1, 5

Questions 12 of 50

Question:A radium \(_{88}R{a^{224}}\) isotope, on emission of an \(\alpha\)-particle gives rise to a new element whose mass number and atomic number will be

Answers Choices:

220 and 86

225 and 87

228 and 88

224 and 86

Questions 13 of 50

Question:During a \(\beta\)-decay the mass of the atomic nucleus

Answers Choices:

Decreases by one unit

Increases by one unit

Decreases by two units

Remains unaffected

Questions 14 of 50

Question:Which one of the following notations shows the product incorrectly

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Questions 15 of 50

Question:A photon of hard gamma radiation knocks a proton out of \(_{12}^{24}Mg\) nucleus to form

Answers Choices:

The isotope of parent nucleus

The isobar of parent nucleus

The nuclide \(_{11}^{23}Na\)

The isobar of \(_{11}^{23}Na\)

Questions 16 of 50

Question:\(_{84}P{b^{210}}{ \to _{82}}P{b^{206}}{ + _2}H{e^4}\). From the above equation, deduce the position of polonium in the periodic table (lead belongs to group IV A)

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Questions 17 of 50

Question:The atomic number of a radioactive element increases by one unit in

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Alpha emission

Beta emission

Gamma emission

Electron capture

Questions 18 of 50

Question:The end product of \((4n+1)\) radioactive disintegration series is

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Questions 19 of 50

Question:In which radiation mass number and atomic number will not change

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\(\alpha\) and \(2\beta\)

Questions 20 of 50

Question:Disintegration constant for a radioactive substance is 0.58\(h{r^{-1}}\). Its half-life period

Answers Choices:

8.2 hr

5.2 hr

1.2 hr

2.4 hr

Questions 21 of 50

Question:Isotopes of an element have

Answers Choices:

Similar chemical properties but different physical properties

Similar chemical and physical properties

Similar physical properties but different chemical properties

Different chemical and physical properties

Questions 22 of 50

Question:Whose number is common in isotopes

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Proton and neutron


Questions 23 of 50

Question:Isotopes are those which contain

Answers Choices:

Same number of neutrons

Same physical properties

Same chemical properties

Different atomic mass

Questions 24 of 50

Question:An element \('A'\) emits an \(\alpha\)-particle and forms \('B'.\,'A'\) and \('B'\) are

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Questions 25 of 50

Question:Isotopes differ in

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Number of protons


Chemical reactivity

Number of neutrons

Questions 26 of 50

Question:The isobars are atoms with the same number of

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Protons and neutrons


Questions 27 of 50

Question:Positron has nearly the same weight as that of

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Questions 28 of 50

Question:In the reaction \(_3L{i^6}+(?)\to{\;_2}H{e^4}+{\;_1}{H^3}\). The missing particle is

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Questions 29 of 50

Question:In the nuclear reaction \(_{92}{U^{238}}{\to_{82}}P{b^{206}}+x{\,_2}H{e^4}+y{\,_{-1}}{\beta^0}\) the value of x and y are respectively ……..

Answers Choices:

8, 6

6, 4

6, 8

8, 10

Questions 30 of 50

Question:If an isotope of hydrogen has two neutrons in its atom, its atomic number and atomic mass number will respectively be

Answers Choices:

2 and 1

3 and 1

1 and 1

1 and 3

Questions 31 of 50

Question:Stable nuclides are those whose n/p ratio is

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Questions 32 of 50

Question:Neutrino has

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Charge +1, mass 1

Charge 0, mass 0

Charge – 1, mass 1

Charge 0 , mass 1

Questions 33 of 50

Question:Electromagnetic radiation with maximum wavelength is

Answers Choices:

Ultraviolet ray




Questions 34 of 50

Question:Neutrons are obtained by

Answers Choices:

Bombardment of Ra with b-particles

Bombardment of Be with \(\alpha \)-particles

Radioactive disintegration of uranium

None of these

Questions 35 of 50

Question:The radiations having high penetrating power and not affected by electrical and magnetic field are

Answers Choices:

Alpha rays

Beta rays

Gamma rays


Questions 36 of 50

Question:Alpha particles are ...... times heavier (approximately) than neutrons

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Questions 37 of 50

Question:Of the following radiations, the one most easily stopped by air is

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Questions 38 of 50

Question:Uranium ultimately decays into a stable isotope of

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Questions 39 of 50

Question:Nuclear theory of the atom was put forward by

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Neils Bohr

J.J. Thomson

Questions 40 of 50

Question:Decrease in atomic number is observed during

Answers Choices:

Alpha emission

Beta emission

Positron emission

Electron capture

Questions 41 of 50

Question:\({C^{14}}\) is radioactive. The activity and the disintegration product are

Answers Choices:

\(\beta\)-active, \(_7{N^{14}}\)

\(\alpha\)- active, \(_7B{e^{10}}\)

Positron active, \(_5{B^{14}}\)

\(\gamma\)- active, \({C^{14}}\)

Questions 42 of 50

Question:Radioactivity of a radioactive element remains \(\frac{1}{{10}}\) of the original radioactivity after 2.303 seconds. The half-life period is

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Questions 43 of 50

Question:The half-life of \(_6{C^{14}}\) if its K or \(\lambda\) is \(2.31\times{10^{-4}}\) is

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Questions 44 of 50

Question:A radioactive isotope has a half-life of 10 days. If today \(125\,mg\)is left over, what was its original weight 40 days earlier

Answers Choices:


600 mg

1 g

1.5 g

Questions 45 of 50

Question:The half-life of the radio element \(_{83}B{i^{210}}\) is 5 days. Starting with 20 g of this isotope, the amount remaining after 15 days is

Answers Choices:

10 g

5 g

2.5 g

6.66 g

Questions 46 of 50

Question:75% of the first order reaction was completed in 32 minutes. When was 50% of the reaction completed

Answers Choices:

24 minutes

16 minutes

8 minutes

4 minutes

Questions 47 of 50

Question:The amount of \(_{53}{I^{128}}\) \({t_{1/2}}=25\) minutes) left after 50 minutes will be

Answers Choices:

One – half

One – third

One – fourth


Questions 48 of 50

Question:If 3/4 quantity of a radioactive element disintegrates in two hours, its half-life would be

Answers Choices:

1 hour

45 minutes

30 minutes

15 minutes

Questions 49 of 50

Question:For a reaction, the rate constant is \(2.34{\sec^{-1}}\). The half-life period for the reaction is

Answers Choices:

0.30 sec

0.60 sec

3.3 sec

Data is insufficient

Questions 50 of 50

Question:\({T_{1/2}}\) of \({C^{14}}\) isotope is 5770 years. time after which 72% of isotope left is

Answers Choices:

2740 years

274 years

2780 years

278 years