Atoms MCQs with Answers

describes the shapes of an atomic orbital.

• A.Principal quantum number
• B.Magnetic quantum number
• C.Azimuthal quantum number
• D.Spin quantum number

Which of the following is the name of the smallest part of the matter discovered by the scientists?

• A.Atom
• B.Electron
• C.Quark
• D.Neutron

The transition absorbing photons of highest frequency in a hydrogen atom is _?

• A.j = 1 to j = 2
• B.j = 2 to j = 1
• C.j = 2 to j = 3
• D.j = 3 to j = 2

The hydrogen-like atom has one electron revolving around a stationary nucleus. The energy required to excite the electron from the second orbit to the third orbit is 42.7 eV. The atomic number of the atom is _?

• A.2
• B.3
• C.4
• D.5

α-rays (Alpha rays) are _?

• A.Positively charged hydrogen nuclei
• B.Negatively charged electrons
• C.Neutral electromagnetic waves
• D.Positively charged helium nuclei

A heavier nucleus contains:

• A.Equal number of neutrons and protons
• B.More neutrons than protons
• C.More protons than neutrons
• D.Only neutrons and no protons

Mechanism for the emission of β⁻ particle from nucleus is that in which?

• A.Neutron is changed into proton
• B.Proton is changed into neutron
• C.Electron is captured by nucleus
• D.Proton and neutron combine

Radioactivity is associated with ?

• A.Decay of Nucleus
• B.Fusion of Atoms
• C.Electron Excitation
• D.Chemical Bonding

In an electronic transition, an atom cannot emit?

• A.Ultraviolet radiation
• B.Infrared radiation
• C.γ-radiations
• D.Visible light

The uranium-238 decays to thorium-234 by process of ?

• A.Neutron emission
• B.Beta radiation
• C.Gamma radiation
• D.Alpha radiation