Chemistry - Radioactivity
Exam Duration: 60 Mins Total Questions : 30
Consider the following statements with reference to X-rays
1. They produce heat when absorbed by matter.
2. They are generated when fast moving electrons strike a metal target.
3. They can penetrate through a thin sheet of aluminum.
Which of the statements given above are correct?
- (a)
1,2 and 3
- (b)
1 and 2
- (c)
2 and 3
- (d)
1 and 3
Which one of the following has the highest frequency?
- (a)
Cosmic rays
- (b)
X-rays
- (c)
Radio waves
- (d)
Microwaves
In an atomic explosion, enormous energy is released which is due to the
- (a)
Conversion of neutrons into protons
- (b)
Conversion of chemical energy into heat energy
- (c)
Conversion of chemical energy into nuclear energy.
- (d)
Conversion of mass into energy.
By which of the following an old written material which cannot be read easily, can be read?
- (a)
Gamma Rays
- (b)
X-rays
- (c)
IR-rays
- (d)
Radio frequency waves.
What is the correct ascending order for frequencies of the following radiations?
1. Visible
2. X-rays
3. Ultraviolet
4. Radio waves
- (a)
1,3,2,4
- (b)
3,2,4,1
- (c)
4,1,3,2
- (d)
4,3,1,2
Which of the following is used as a coolant in nuclear reactors?
- (a)
Heavy water
- (b)
Cadmium
- (c)
Liquid sodium
- (d)
Graphite
Which of the following is good nuclear fuel?
- (a)
Uranium-238
- (b)
Neptunium-239
- (c)
Thorium-236
- (d)
Plutonium-239
Consider the following statements:
1. X-rays can pass through aluminum.
2. X-rays can be deflected by a magnetic field.
3. X-rays move with a velocity less than the velocity of ultraviolet rays in the vacuum.
Which of the statements given above are correct?
- (a)
1,2 and 3
- (b)
Only 1
- (c)
2 and 3
- (d)
1 and 2
Which one of the following is not radioactive?
- (a)
Astatine
- (b)
Francium
- (c)
Tritium
- (d)
Zirconium
Assertion (A): X-rays are used for studying the structure of crystals.
Reason (R): The difference between the atoms of crystals is of the order of wavelength of X-rays
- (a)
Both A and R are true and R is the correct explanation of A
- (b)
Both A and R are true but R is not the correct explanation of A
- (c)
A is true, but R is False
- (d)
A is false, but R is true
The function of heavy water in a nuclear reactor is to
- (a)
slowing down the speed of neutrons.
- (b)
increase the speed of neutrons.
- (c)
cooling down the reactor
- (d)
stop the nuclear reaction
Radio Carbon dating is used to estimate the age of
- (a)
rocks
- (b)
old monuments
- (c)
fossils
- (d)
living trees
The age of Earth can be estimated by
- (a)
Radio Carbon dating
- (b)
Radio Uranium dating
- (c)
By its magnetic field
- (d)
By its precession movement.
The Alpha particle carries two positive charges. Its mass is very nearly equal to that of
- (a)
two protons
- (b)
an atom of helium
- (c)
the sum of masses of two positrons and two neutrons.
- (d)
two positions as each positron carry a single positive charge.
The difference between the nuclear reactor and atomic bomb is that
- (a)
no chain reaction takes place in a nuclear reactor is not controlled.
- (b)
the chain reaction in the nuclear reactor is controlled
- (c)
the chain reaction in the nuclear reactor is not controlled
- (d)
the no-chain reaction takes place in atomic bomb while it takes place in a nuclear reactor
Radioactivity is a natural disintegration of nuclei of heavy elements because only heavy elements
- (a)
Contain alpha particles
- (b)
Can have unstable nuclei with neutron-proton ratio being quite uneven
- (c)
contain excess of neutrons
- (d)
can produce lead as the end product
Which one among the following is the mean life of radioactive elements?
- (a)
Equal to half-life
- (b)
Less than half-life
- (c)
0.693t1/2
- (d)
1.44 t1/2
Consider the following statements:
1. Nuclear reactions involve changes in the nucleus of an atom.
2. The rate of a nuclear reaction is increased by the addition of a catalyst.
3. A nuclear reaction is unaffected by the chemical state of the atoms involved.
4. Nuclear reactions of the same element vary according to which isotope involved.
Which of the statements about nuclear reactions given above are correct?
- (a)
Only 1
- (b)
1 and 2
- (c)
1, 3 and 4
- (d)
2, 3 and 4
Consider the following statements:
1. Radioactive decay is the process by which unstable atomic nuclei emit subatomic particle or radiation.
2. When a radioactive nucleus decays, its nucleus breaks up, emits an alpha particle or beta particle and energy, and forms a new atom of a different element.
Which of the statements given above are correct?
- (a)
Only 1
- (b)
Only 2
- (c)
1 and 2
- (d)
None of these
Which of the properties of radioisotopes make them useful as traces in medical or agricultural applications?
1. Their chemical behavior is the same as a non-radioactive isotope.
2. They emit various types of radiation.
3. The nuclear reaction is unaffected by the chemical state of isotope.
- (a)
Only 1
- (b)
1 and 3
- (c)
1 and 2
- (d)
All of these
Select the correct statement
- (a)
MRI uses radio waves to stimulate certain nuclei in the presence of magnetic field
- (b)
P-32 is used for leukemia therapy
- (c)
I-123 is used in imaging the brain
- (d)
All of the above
Which one of the following reactions is the main cause of the energy radiation from the sun?
- (a)
Fusion reaction
- (b)
Fission reaction
- (c)
Chemical reaction
- (d)
Diffusion reaction
Consider the following statements:
1. Radioactivity tracers are commonly used in the medical field and also in the study of plants and animals.
2. Radiation is used and produced in nuclear reactors, which controls fission reactions to produce energy and new substances from the fission products.
3. Radiation is also used to sterilize medical instrument and food.
Which of the statements given above are correct?
- (a)
1 and 2
- (b)
1 and 3
- (c)
2 and 3
- (d)
1, 2 and 3
Assertion (A): In Beta decay, the direction of the recoiling daughter nucleus is opposite to that of the beta particle emitted.
Reason (R): In Beta decay, beta particles are not emitted with a fixed energy.
- (a)
Both A and R are true and R is the correct explanation of A
- (b)
Both A and R are true but R is not the correct explanation of A
- (c)
A is true, but R is False
- (d)
A is false, but R is true.
Assertion (A): All compounds contain more than one element.
Reason (R): All compounds are heterogeneous mixtures.
- (a)
Both A and R are true and R is the correct explanation of A
- (b)
Both A and R are true but R is not the correct explanation of A
- (c)
A is true, but R is False
- (d)
A is false, but R is true.
Which one of the following is used as a moderator in the nuclear reactor?
- (a)
Thorium
- (b)
Graphite
- (c)
Radium
- (d)
Ordinary Water
The function of heavy water in a nuclear reactor is to
- (a)
slow down the speed of neutrons
- (b)
increase the speed of neutrons
- (c)
cool down the reactor
- (d)
stop the nuclear reaction
Which of the following isotopes of carbon are used in carbon dating?
- (a)
6C12 Only
- (b)
6C13 Only
- (c)
6C14 Only
- (d)
6C12 and 6C14
Assertion (A): Alpha Particles and Beta Particles can be detected by a Geiger counter.
Reason (R): Neutron can be detected by conversion into the Alpha particle by the addition of 510 B.
- (a)
Both A and R are individually true and R is the correct explanation of A
- (b)
Both A and R are individually true but R is not the correct explanation of A
- (c)
A is true, but R is False
- (d)
A is false, but R is true.
Match the column I and Column II and select the correct answer using the code given below:
Column I ( Nuclear reactor components) | Column II (Substance used) |
A. Moderator | 1. Sodium |
B. Control rods | 2. Uranium |
C. Fuel rods | 3. Graphite |
D. Coolant | 4. Boron |
- (a)
A B C D 3 4 2 1 - (b)
A B C D 1 2 4 3 - (c)
A B C D 3 1 2 4 - (d)
A B C D 2 4 1 3