Lecture 2 8/24/22 Flashcards
____ are substances comprised of two or more elements in a fixed ratio
Compounds
C.H.O.P.S.N. / the most important elements
Carbon, hydrogen, oxygen, phosphorous, sulfur, nitrogen
The number of protons in the nucleus is the _____
Atomic Number
The total number of neutrons + protons is the _____
Mass number
These varying forms of an element are called _____
Isotopes
_______ describe the average distance of a subset of electron from the nucleus
Electron shells
_____ are attractions between compounds which are the result of their associated properties
Chemical bonds
______are formed when valence electrons are shared by two atoms and are the strongest type of bond
Covalent bonds
_____ are formed as the result covalent bonds
Molecules
Certain elements attract electrons more strongly, this property is called _____
electronegativity
An equal sharing of electrons results in a _____
nonpolar covalent bond
In cases where electrons are unequally draw to certain elements in a molecule you end up with a _____
Polar covalent bond
_____ form between elements/molecules which have opposite charges (ions)
Ionic bonds
positive elements/molecules
Cations
negative elements/molecules
anions
Ionic bonds often form ____, which are not molecules strictly speaking
Salts
Elements/molecules with polar covalent bonds attract one another in what are known as ____
Hydrogen bond
However, even non-polar elements/molecules may attract one another if sufficiently dense in attractions known as _____
Van der Waals Forces
Oxygen is highly electronegative, the result being that water is very much a ______
polar molecule
Water molecules stick to one another in a phenomenon known as _____
Cohesion
This wide attraction to other substances is known as _____
Adhesion
______ is essentially a measure of kinetic energy
Temperature
_____ describes the amount of heat required to heat one gram of water by 1°
Calorie
______ is the amount of hear required to change one gram of substance by 1°
Specific heat
water has a high ______, that is the amount of heat required for a gram of liquid to convert to a gas
heat of vaporization
The _____ is the dissolving agent
Solvent
The _____is the substance being dissolved
Solute
A solution in which water is the solvent is known as an ______
Aqueous solution
The molecule that lost the H atom becomes a ____(OH-)
Hydroxide
The molecule that gained the the H atom becomes a ____
Hydronium
