Protons
Positive particles in the nucleus. Their count is the atomic number.
Loading
Preparing your study cards
Loading
Preparing your study cards
Chemistry · Unit 01
Proton count identifies an element. Neutrons distinguish isotopes, electrons control net charge, and chemical bonds join atoms into molecules and other structures.
Positive particles in the nucleus. Their count is the atomic number.
Uncharged nuclear particles. Different counts create isotopes.
Negative particles around the nucleus. Gains or losses create ions.
Retrieval practice
Recall each idea before revealing the answer. The associated educational section is attached to every card.
The smallest unit of an element that retains that element's chemical identity.
Atoms contain a tiny nucleus surrounded by electrons, and their proton count determines the element.
Protons and neutrons.
Nearly all atomic mass is concentrated in the nucleus, while electrons occupy the surrounding region.
In the region surrounding the nucleus, described by electron probability distributions.
The modern model does not treat electrons as miniature planets following fixed circular paths.
The number of protons in each atom of that element.
Changing the proton count changes the element's identity.
Add the number of protons and neutrons in its nucleus.
Electrons have much less mass and are not included in the mass number.
They have the same number of protons but different numbers of neutrons.
Isotopes share an atomic number but have different mass numbers.
The positive proton charges and negative electron charges balance.
Neutrons have no net electric charge.
An atom or molecule with a net electric charge because it has gained or lost electrons.
Ordinary ion formation changes electron count rather than proton count.
Cations have a positive charge; anions have a negative charge.
Losing electrons produces a cation, while gaining electrons produces an anion.
Two or more atoms joined by chemical bonds as a discrete unit.
The atoms can belong to the same element or to different elements.
The number of atoms of the element immediately before that subscript.
In H₂O, the 2 applies to hydrogen; oxygen has an implied count of one.
The discovery of subatomic particles, including electrons, protons, and neutrons.
Later experiments refined early atomic theory into a model with internal structure.
Source transparency
Lilerno wrote the lesson and cards in original language. These materials were used only to check scientific facts; their text, diagrams, and media are not reproduced.
OpenStax, Rice University
Authors: Paul Flowers, Klaus Theopold, Richard Langley, William R. Robinson
Referenced for fact checking: OpenStax, Chemistry 2e, section 2.2, OpenStax at Rice University. Lilerno does not reproduce its text or media.
OpenStax, Rice University
Authors: Paul Flowers, Klaus Theopold, Richard Langley, William R. Robinson
Referenced for fact checking: OpenStax, Chemistry 2e, section 2.3, OpenStax at Rice University. Lilerno does not reproduce its text or media.
OpenStax, Rice University
Authors: Paul Flowers, Klaus Theopold, Richard Langley, William R. Robinson
Referenced for fact checking: OpenStax, Chemistry 2e, section 2.4, OpenStax at Rice University. Lilerno does not reproduce its text or media.