Understanding Atomic Structure

What is the basic unit of matter?

• Compound

• Molecule

• Atom

• Cell

Who proposed the planetary model of the atom?

• J.J. Thomson

• James Chadwick

• Niels Bohr

• Ernest Rutherford

What are the three main subatomic particles?

• Protons, neutrons, and electrons

• Neutrons, electrons, and muons

• Protons, electrons, and positrons

• Protons, quarks, and neutrinos

What is the charge of a proton?

• 0 elementary charge

• -1 elementary charge

• +2 elementary charge

• +1 elementary charge

What is the mass of a neutron compared to a proton?

• The mass of a neutron is equal to that of a proton.

• The mass of a neutron is slightly greater than that of a proton.

• The mass of a neutron is less than that of a proton.

• The mass of a neutron is significantly greater than that of a proton.

What is the significance of the atomic number?

• The atomic number is significant because it defines the element and its properties.

• It indicates the mass of the element.

• It represents the number of neutrons in the nucleus.

• It determines the color of the element.

How do isotopes of an element differ?

• Isotopes vary in their electron count.

• Isotopes have different chemical properties.

• Isotopes differ in the number of neutrons.

• Isotopes differ in the number of protons.

What is the role of electrons in chemical bonding?

• Electrons are primarily responsible for the mass of an atom.

• Electrons do not affect the stability of atoms.

• Electrons play a crucial role in forming chemical bonds by either being shared or transferred between atoms.

• Electrons are only involved in nuclear reactions.

What is the concept of electron shells?

• Electron shells are defined as the orbits around an atom's nucleus where electrons reside, organized by energy levels.

• Electron shells are the regions where neutrons are located.

• Electron shells are the particles that form chemical bonds.

• Electron shells are the protons in an atom's nucleus.

How does the quantum mechanical model differ from earlier models?

• The quantum mechanical model uses fixed orbits like earlier models.

• The quantum mechanical model incorporates wave-particle duality and probability distributions, unlike earlier models that used fixed orbits.

• The quantum mechanical model is based solely on classical mechanics.

• Earlier models incorporate wave-particle duality and probability distributions.