Chapter 2 Flashcards
(22 cards)
Matter
Anything that has mass and occupies space. It is made up of atoms and molecules.
Mass
The amount of matter in an object or substance. It is typically measured in grams or kilograms.
Atomic number
The number of protons in an atom’s nucleus.
Element
A pure substance made of only one kind of atom.
Orbitals
Regions around an atom’s nucleus where electrons are likely to be found.
Octet rule
Atoms are most stable with 8 electrons in their outer shell.
Free radical
A molecule with an unpaired electron, making it very reactive.
Ion
An atom or molecule with a charge because it gained or lost electrons.
Cation
A positively charged ion that has lost one or more electrons.
Anion
A negatively charged ion that has gained one or more electrons.
Molecule
Two or more atoms bonded together.
Compound
A substance made of two or more different elements chemically bonded
Electronegativity
An atom’s ability to attract electrons in a bond.
Polarity
A difference in electrical charge across a molecule.
Hydrophobic
“Water-fearing”; substances that do not dissolve in or interact with water, typically nonpolar molecules like oils.
Hydrophilic
“Water-loving”; substances that interact or dissolve well in water, typically polar molecules or ions.
Solute
The substance that is dissolved in a solution.
Solution
A mixture where one substance is dissolved in another.
Cohesion
The attraction between molecules of the same substance.
Adhesion
The attraction between molecules of different substances.
pH
A scale that measures how acidic or basic a solution is.
buffer
A substance that helps maintain a stable pH in a solution
