Atomic Structure and Properties

What are atoms primarily made of?

• Molecules, compounds, and mixtures

• Protons, electrons, and neutrons

• Cells, tissues, and organs

• Quarks, leptons, and bosons

What determines the identity of an element?

• The number of electrons

• The number of neutrons

• The number of protons

• The size of the atom

What is another name for the number of protons in an atom?

• Atomic mass

• Atomic number

• Isotope number

• Electron count

Why do electrons orbit the nucleus of an atom?

• They are attracted to the positive charge of protons.

• They are repelled by the negative charge of neutrons.

• They are pushed by the strong nuclear force.

• They are pulled by gravity.

What is the primary role of neutrons in an atom's nucleus?

• To attract electrons to the nucleus.

• To provide a negative charge to the nucleus.

• To act as "glue" and hold protons together.

• To determine the element's atomic number.

Who was the first to propose a scientific atomic theory?

• Democritus

• John Dalton

• J.J. Thomson

• Ernest Rutherford

What did J.J. Thomson's Plum Pudding Model suggest about the structure of the atom?

• Atoms are indivisible particles.

• Atoms have a small, dense nucleus.

• Atoms are a sphere of positive charge with embedded electrons.

• Electrons travel in specific orbits around the nucleus.

What was the significant finding of Ernest Rutherford's Gold Foil Experiment?

• Atoms are indivisible and indestructible.

• Atoms have a small, dense nucleus and are mostly empty space.

• Electrons exist in probability clouds around the nucleus.

• Atoms emit light in discrete spectra.

How did Niels Bohr refine the atomic model?

• By proposing atoms are indivisible.

• By suggesting electrons travel in specific orbits with fixed energy levels.

• By introducing the concept of probability clouds for electrons.

• By depicting the atom as a sphere of positive charge.

What is the modern understanding of atomic structure based on?

• Dalton's Atomic Theory

• The Plum Pudding Model

• Quantum mechanics

• The Bohr Model