Chemistry - Nuclear Chemistry
Exam Duration: 45 Mins Total Questions : 30
Initial mass of a radioactive element is 16 gm. How many grams of it would be left after 24 years if its half life is 8 years?
- (a)
8
- (b)
4
- (c)
2
- (d)
1
Proton is
- (a)
nucleus of deuterium
- (b)
Ionised hydrogen molecule
- (c)
ionised hydrogen atom
- (d)
an alpha particle
Gamma rays are essentially
- (a)
electromagnetic radiations
- (b)
high speed electrons
- (c)
high speed neutrons
- (d)
high speed protons
The isotope 40K transforms into the isotope 40Ca. What kind of radioactive decay occurs in this case?
- (a)
k-electron capture
- (b)
\(\alpha-decay\)
- (c)
\(\beta-decay\)
- (d)
positron decay
Which one of the following statements is true?
- (a)
The difference between mass of an atom and the sum of masses of neutrons and protons present in it is called mass defect.
- (b)
Binding energy is the amount energy lost in the formation of nuclide from its nucleons.
- (c)
Uranium-lead dating is a technique used for estimating the age of rocks and minerals.
- (d)
ALL OF THE ABOVE
The isotopic mass of \(_{ 92 }^{ 238 }{ U }\) is 238. 15 amu. its packing fraction is
- (a)
1.25
- (b)
0.125
- (c)
5.25
- (d)
9.5
A device used for the measurement of radioactivity is
- (a)
mass spectrometer
- (b)
cyclotron
- (c)
nuclear reactor
- (d)
G.M. Counter
Isobars are produced as a result of emission of
- (a)
\(\alpha\)-particle
- (b)
\(\beta\) -particle
- (c)
X-rays
- (d)
\(\gamma\)-rays
The radio isotope used in the treatment of cancer:
- (a)
C-12
- (b)
Co-60
- (c)
I-131
- (d)
P-32
The artificial transmutation of elements was discovered by
- (a)
Bohr
- (b)
Rutherford
- (c)
J.J. Thomson
- (d)
Madam Curie
Which of the following have been prepared artificially?
- (a)
Uranium and Thorium
- (b)
Einsteinium and Fermium
- (c)
Radium and Polonium
- (d)
Thorium and Hafnium
The half-time of a radioactive element depends on
- (a)
amount of element
- (b)
pressure
- (c)
temperature
- (d)
NONE OF THE ABOVE
Which of the radioactive isotopes is used for temperature control in blood disease?
- (a)
P-32
- (b)
H-3
- (c)
Rn-223
- (d)
I-131
An isotope is formed when successive radioactive emissions of an elements are
- (a)
\(\alpha, \alpha, \alpha\)
- (b)
\(\alpha, \beta, \alpha\)
- (c)
\(\alpha, \beta, \beta\)
- (d)
\(\beta, \beta, \beta\)
If the half-life for 14C is 5770 years, the n t3/4 is
- (a)
5760 X \(\frac { 3 }{ 4 } \) years
- (b)
5760 X 1 year
- (c)
5760 X2 years
- (d)
5760 X \(\frac { 4 }{ 3 } \) years
The half-life of \(_{ 84 }^{ 216 }{ Po }\) is 0.16 sec. How long will it take a sample of this nucleus to decay to 90 %
- (a)
0.16 sec
- (b)
0.32 sec
- (c)
0.48 sec
- (d)
0.53 sec
Number of neutrons in a parent nucleus X, which gives \(_{ 7 }^{ 14 }{ N }\) after two successive \(\beta \) - emissions would be
- (a)
6
- (b)
7
- (c)
8
- (d)
9
The t1/2 of radioactive element is 140 days. In 560 days a sample of this element would be reduced to .... of its initila mass.
- (a)
\(\frac { 1 }{ 2 } \)
- (b)
\(\frac { 1 }{ 4 } \)
- (c)
\(\frac { 1 }{ 8 } \)
- (d)
\(\frac { 1 }{ 16 } \)
The radioactive decay of \(_{ 35 }^{ 88 }{ X }\) by \(\beta \) -particle emission produces an unstable nucleus which spontaneously emits a neutron. The final product is
- (a)
\(_{ 37 }^{ 88 }{ X }\)
- (b)
\(_{ 35 }^{ 89 }{ Y }\)
- (c)
\(_{ 34 }^{ 88 }{ Z }\)
- (d)
\(_{ 36 }^{ 87 }{ W }\)
Insert the missing figure in the following \(_{ 25 }^{ 55 }{ Mn }\) (n, \(\gamma\) ) \(\rightarrow \)
- (a)
\(_{ 25 }^{ 56 }{ Mn }\)
- (b)
\(_{ 24 }^{ 55 }{ Cr }\)
- (c)
\(_{ 25 }^{ 55 }{ Mn }\)
- (d)
\(_{ 24 }^{ 56 }{ Cr }\)
If half-life of substance is 5 years, then the total amount of substance left after 15 years, when initial amount is 64 gram.
- (a)
16 g
- (b)
2 g
- (c)
32 g
- (d)
8 g
Which of the following is incorrect?
- (a)
45SC + \(_{ 0 }^{ 1 }{ n }\) \(\rightarrow\) 45Cu + \(_{ 1 }^{ 0 }{ n }\)
- (b)
209Bi + 2H \(\rightarrow\) 210Po + \(_{ 0 }^{ 1 }{ n }\)
- (c)
7Li + 1H \(\rightarrow\) 7Be + \(_{ 0 }^{ 1 }{ n }\)
- (d)
75As + 4He \(\rightarrow\) 78Br + \(_{ 0 }^{ 1 }{ n }\)
What is X in the nuclear reaction? 14N + X \(\rightarrow\) 14C + 1H
- (a)
1H
- (b)
\(_{ +1 }^{ 0 }{ e }\)
- (c)
\(_{ 0 }^{ 1 }{ n }\)
- (d)
\(_{ 1 }^{ 0 }{ e }\)
Which of the following will be called projectile in the nucleus reaction? 14N + 4He \(\rightarrow\) 17O + 1H
- (a)
14N
- (b)
4He
- (c)
17O
- (d)
1H
Which one of the following projectiles can be used to bombard 7N to give \(_{ 8 }^{ 17 }{ O }\)?
- (a)
\(_{ 1 }^{ 2 }{ H }\)
- (b)
\(_{ 1 }^{ 1 }{ H }\)
- (c)
\(_{ 2 }^{ 4 }{ He }\)
- (d)
\(_{ 0 }^{ 1 }{ n }\)
\(_{ 92 }^{ 238 }{ U }\) during a series of \(\alpha\) and \(\beta\) decay; loses in all 8\(\alpha\) and 6\(\beta\) particles. The atomic mass and number of the end product would be
- (a)
206, 82
- (b)
212, 90
- (c)
227, 76
- (d)
238, 90
In the nuclear reaction \(_{ 92 }^{ 238 }U\) \(\rightarrow\) \(_{ 82 }^{ 206 }Pb\) the number of \(\alpha\) and \(\beta\) particles emitted are
- (a)
7\(\alpha\), 5\(\beta\)
- (b)
6\(\alpha\), 4\(\beta\)
- (c)
4\(\alpha\), 3\(\beta\)
- (d)
8\(\alpha\), 6\(\beta\)
\({ 6 }^{ C^{ 14 } }\)in the upper atmosphere is formed by the action of neutrons on
- (a)
\(_{ 7 }^{ 14 }{ N }\)
- (b)
\(_{ 8 }^{ 17 }{ O }\)
- (c)
\(_{ 6 }^{ 12 }{ C }\)
- (d)
\(_{ 8 }^{ 18 }{ O }\)
1 mole of an \(\alpha \)-emiting nuclide \(_{ Z }^{ A }{ X }\) (half-time 10 hrs) was placed in sealed container .4.52 x 1023 helium atoms will accumlate in the container in
- (a)
4.552 hr
- (b)
9.40 hr
- (c)
10.00 hr
- (d)
20.00 hr
Energy released in the nuclear fusion reaction is
\(_{ 1 }^{ 2 }{ H }+_{ 1 }^{ 3 }{ H }\rightarrow _{ 2 }^{ 4 }{ He }+_{ 0 }^{ 1 }{ n }\)
Atomic mass of \(_{ 1 }^{ 2 }{ H=2.014 }\); \(_{ 1 }^{ 3 }{ H=3.016 }\) \(_{ 2 }^{ 4 }{ He=4.003 }\), \(_{ 0 }^{ 1 }{ n=1.009 }\) (all in amu)
- (a)
16.06 MeV
- (b)
500 J
- (c)
4X106 kcal.
- (d)
8.30 eV