Atoms of an element differ from those of all other elements in.
1.atomic number and electronic configuration
2. number of neutrons and number of valence electrons
3.atomic number and number of valence electrons
4.number of neutrons and electronic configuration
Posted Date:-2021-03-07 03:37:12
The isotope of uranium capable of sustaining chain reaction is
1.U-235
2.U-245
3.U-239
4.U-238
Posted Date:-2021-03-07 03:37:12
In an atomic nucleus, neutrons and protons are held together by
1. gravitational forces
2.exchange forces
3. coulombic forces
4.magnetic forces
Posted Date:-2021-03-07 03:37:12
The dark lines in the solar spectrum are due to
1.absorption of corresponding wavelengths by the outer layers of the sun
2.destructive interference between waves of certain definite wavelengths
3.absorption of corresponding wavelengths by the prism used in the photograph
4.absence of corresponding wavelengths from the light emitted by the core of the sun
Posted Date:-2021-03-07 03:37:12
According to Avogadro's Hypothesis, the smallest particle of an element or a compound, that can exist independently, is called ____ .
1.a molecule
2.a cation
3.an anion
4.an atom
Posted Date:-2021-03-07 03:37:12
Atoms are composed of
1.electrons and protons
2.electrons only
3.protons only
4.electrons and nuclei
Posted Date:-2021-03-07 03:37:12
How many colours the sunlight spectrum has?
1.Three
2.Seven
3.Four
4.Five
Posted Date:-2021-03-07 03:37:12
Which of the following is used as a moderator in nuclear reactor?
1.Thorium
2.Graphite
3.Radium
4.Ordinary water
Posted Date:-2021-03-07 03:37:12
In an atomic explosion, enormous energy is released which is due to
1.conversion of chemical energy into heat energy
2. conversion of mechanical energy into nuclear energy
3.conversion of mass into energy
4.conversion of neutrons into protons
Posted Date:-2021-03-07 03:37:12
Mesons are found in
1. Laser beam
2.X-rays
3.Gamma rays
4.Cosmic rays
Posted Date:-2021-03-07 03:37:12
No two electrons in an atom can have the same set of four quantum numbers' is
1.Newton's law
2. Bohr's law
3.Aufbau principle
4.Pauli's exclusion principle
Posted Date:-2021-03-07 03:37:12
Nuclear fission is caused by the impact of
1.neutron
2.proton
3.deuteron
4.electron
Posted Date:-2021-03-07 03:37:12
sotopes are separated by
1.crystallisation
2.sublimation
3.distillation
4.filtration
Posted Date:-2021-03-07 03:37:12
The age of most ancient geological formations is estimated by
1.Ra - Si method
2.Potassium - argon method
3.C14 method
4.Uranium - lead method
Posted Date:-2021-03-07 03:37:12
The wavelength of X-rays is of the order of
1.10 micron
2.1 angstrom
3.1 cm
4.1 m
Posted Date:-2021-03-07 03:37:12
What is the wavelength of visible spectrum?
1.8500 - 9800 angstrom
2.7800 - 8000 angstrom
3.3900 - 7600 angstrom
4.1300 - 3000 angstrom
Posted Date:-2021-03-07 03:37:12
Which among the following is a positively charged particle emitted by a radioactive element?
1. Beta ray
2. Alpha ray
3.Cathode ray
4.Gamma ray
Posted Date:-2021-03-07 03:37:12
Which of the following has a least penetrating power?
1. All have same penetrating power
2.Beta Particles
3.Alpha particles
4.Gamma rays
Posted Date:-2021-03-07 03:37:12
Which of the following rays are more penetrating?
1.Beta rays
2.Alpha rays
3.Gamma rays
4.X-rays
Posted Date:-2021-03-07 03:37:12
Which of the following shows the masses of the three elementary particles in decreasing order?
1.Leptons, Baryons, Mesons
2.Mesons, Baryons, Leptons
3.Baryons, Mesons, Leptons
4.Leptons, Mesons Baryons
Posted Date:-2021-03-07 03:37:12
Which radioactive pollutant has recently drawn to public, due to its occurrence in the building material?
1.Thorium
2.Radium
3.Plutonium
4.Radan
Posted Date:-2021-03-07 03:37:12
Who suggested that most of the mass of the atom is located in the nucleus?
1.Thompson
2.Bohr
3.Rutherford
4.Einstein
Posted Date:-2021-03-07 03:37:12