Atomic Structure Quiz

Atoms are the tiny building blocks that make up all ______.

The particulate nature of matter refers to materials being made up of small ______.

Democritus theorized that tiny particles could not be broken down into even smaller ______.

John Dalton's atomic theory states that all matter is made up of very small particles called ______.

Cathode rays are streams of negatively charged particles called ______.

J.J. Thomson found that the rays were attracted to the positive ______.

Thomson could cancel out the attractive forces using a ______ field.

William Crookes demonstrated that cathode rays travel in ______ lines.

Robert Millikan conducted the oil drop experiment to determine the charge on an ______.

Millikan calculated the charge on an electron as 1.6 x 10^[-blank] coulomb.

In 1898, J.J. Thomson proposed the ‘Plum Pudding’ model of the ______.

Ernest Rutherford discovered the ______ by bombarding gold foil with positively charged alpha particles.

Rutherford concluded that most of the atom is made up of ______ space.

James Chadwick discovered the ______ in 1932 by bombarding beryllium with alpha particles.

The small positively charged particles discovered by Rutherford are called ______.

In Millikan's experiment, oil droplets became negatively charged by picking up ______.

Atomic Structure

Atoms are the fundamental building blocks of matter
Democritus (400 BC) theorized that matter was composed of indivisible particles
John Dalton (1808) proposed an atomic theory: all matter is composed of atoms, atoms are indivisible, and atoms of the same element are identical.
William Crookes (1875) experimented with cathode rays, observing they traveled in straight lines, were deflected by electric and magnetic fields, and had enough energy to move a paddle wheel.
Cathode rays are streams of negatively charged particles called electrons.
J.J. Thomson (1897) discovered the electron, determining the ratio of its charge to mass. Atoms are divisible
Thomson proposed the "plum pudding" model: a diffuse positive charge with electrons embedded within.
Robert Millikan (1909) determined the charge of an electron accurately
Ernest Rutherford (1909) discovered the nucleus by bombarding gold foil with alpha particles.
Most alpha particles passed straight through, some were deflected at large angles, and some bounced back.
Rutherford concluded that the atom is mostly empty space with a dense, positively charged nucleus.
James Chadwick (1932) discovered the neutron, a particle with no charge and roughly the same mass as a proton.

Subatomic Particles

Proton: Positively charged particle, located in the nucleus, relative mass of 1, relative charge of +1.
Neutron: Uncharged particle, located in the nucleus, relative mass of 1, relative charge of 0.
Electron: Negatively charged particle, located outside the nucleus, relative mass of very small, relative charge of -1.

Test your knowledge on the foundations of atomic structure, including historical theories and discoveries by key scientists. This quiz covers concepts from early atomic theory to the modern understanding of atoms, their components, and structure.