Atoms MCQs with Answers

The scientist Chadwick in 1932 discovered?

• A.Electron
• B.Neutron
• C.Proton
• D.Positron

What can be deduced from the symbol ⁴₂He?

• A.An atom of helium contains two electrons
• B.An atom of helium contains four protons
• C.An atom of helium contains two neutrons
• D.An atom of helium contains four neutrons

The number shown below the symbol of element is called?

• A.Atomic Number
• B.Mass Number
• C.Valency
• D.Isotope Number

What is the charge on a neutron?

• A.Positive charge
• B.Negative charge
• C.No charge
• D.Both positive and negative charge

Bohr model defines angular momentum as l = nh/2π, but in Schrodinger wave mechanics it is ?

• A.√l(l + 1) h/2π
• B.l(l + 1) h/2π
• C.(l + 1) h/2π
• D.√l(l - 1) h/2π

If an electron has zero orbital angular momentum, the magnitude of its magnetic dipole moment equals:

• A.0
• B.Bohr magneton
• C.2 Bohr magnetons
• D.Nuclear magneton

Isotopes are atoms of the same element with different numbers of ?

• A.Protons
• B.Electrons
• C.Neutrons
• D.Positrons

Atoms which lose electrons will become positively charged ion and they are known as?

• A.Cations
• B.Anions
• C.Isotopes
• D.Neutrons

Who developed the atomic theory?

• A.Niels Bohr
• B.J.J. Thomson
• C.Ernest Rutherford
• D.John Dalton

Noble gases are stable because they contain _?

• A.8 electrons in valence shell
• B.2 electrons in valence shell
• C.6 electrons in valence shell
• D.No electrons in valence shell