Introduction to Chemistry and Water Properties

Vocabulary flashcards covering atomic structure, electron shells, the periodic table, chemical bonds, and the key properties of water based on the lecture notes.

Carbon 14

A radioactive isotope of carbon present at consistent levels in living organisms that can be measured to date fossils based on how much of it has decayed.

Bohr model

A simplified model of atomic structure resembling a solar system, where electrons travel around the nucleus at high speeds in designated energy shells.

Valence shell

The outermost electron shell of an atom, which is the only shell responsible for chemical reactivity.

Mendeleev

The scientist who devised the periodic table of elements around 1869 by arranging known elements by size, reactivity, and repeating patterns.

Scandium

An element discovered ten years after Mendeleev predicted its existence, having a mass of 45, 21 protons, and three valence electrons.

Ionic interaction

A chemical reaction where one atom gives away an electron to another atom, resulting in oppositely charged ions that attract one another.

Electronegativity

The measure of an atom's attraction or pull on electrons, which is very high in elements like oxygen and fluorine.

Polar molecule

A molecule with an uneven distribution of electrical charge, resulting in one side being partially negative and another side being partially positive.

Tetrahedral shape

A four-sided triangular pyramid geometry that allows four electron pairs to remain as far apart from each other as possible in three-dimensional space.

Hydrogen bond

A temporary attraction formed between a partially positive atom (usually hydrogen) and a partially negative atom on another molecule or region.

Triple covalent bond

The strongest chemical bond in biology, formed by sharing three sets of electrons, famously found holding atmospheric nitrogen together.

Van der Waals interactions

The weakest biological interactions, caused by temporary momentary shifts of electrons to one side of an atom's nucleus.

Sphere of hydration

A cluster of water molecules that completely surrounds a dissolved ion, orienting partial charges toward the ion's opposite full charge.

Cohesion

The property of water molecules sticking to other water molecules via hydrogen bonds.

Adhesion

The property of water molecules sticking to other surfaces or molecules that are polar or partially polar.