Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
42 Cards in this Set
- Front
- Back
Matter |
anything that has mass and occupies space. |
|
Elements |
pure chemical substance made of atoms with the same # of protons in their nuclei. |
|
Atomic Symbol |
shorthand method used for representing an element. |
|
Atomic Number |
number of protons in the nucleus of an atom. |
|
Atomic Mass |
the mass of the subatomic particles in an atom. |
|
Atoms |
smallest unit of matter non-divisible by normal chemical and physical means. |
|
Protons |
positively charged subatomic particles (inside the nucleus). |
|
Neutrons |
uncharged particles (inside the nucleus). |
|
Electrons |
negatively charged subatomic particles (outside the nucleus). |
|
Orbitals |
regions around the nucleus where electrons are likely to be found. |
|
Electron Shells |
orbitals are located here. |
|
Isotopes |
atoms of the same element with differing numbers of neutrons in their nuclei. |
|
Properties of Isotopes |
1. Many are unstable in the wild. 2. Lose energy by emitting small amounts of subatomic particles and/or radiation. 3. The time they exist is measured in half-lives. |
|
Molecules |
two or more atoms bonded together. Atoms may be either of same element or different ones. |
|
Compound |
atoms of two or more different elements bonded together. |
|
Chemical Bonds |
energy relationships between electrons. |
|
Valence Electrons |
electrons in the outermost energy shell. |
|
Octet Rule |
atoms are most stable when they have eight electrons in their outermost energy shell. Exception: If it only has one outer shell, the it's full with two electrons. |
|
Ion |
charged atom. |
|
Ionic Bond (general) |
weak bond that is easily soluble in water. Atoms accept electrons to satisfy the Octet Rule, resulting in net electrical charge on the the atoms involved. |
|
Ionic Bond (charges) |
formed when ions of opposite charge are attracted to each other. |
|
Ionic Bond (ions) |
form when cation (+) bonds to an anion(-). |
|
Cation |
positively charged ion. |
|
Anion |
negatively charged ion. |
|
Covalent bond |
strong bond where atoms share electrons to satisfy the octect rule. Visually represented by dotted lines. |
|
Electronegativity |
the ability of an atom to attract electrons towards its nucleus when forming bonds with other atoms. |
|
Nonpolar Covalent Bond |
bond that forms between atoms of similar electronegativity. Electrons are shared equally between atoms. No partial charges. |
|
Polar Covalent Bonds |
bond that forms between atoms with different electronegativities. Electrons are not shared equally between atoms. Shared electrons are closer to the nucleus with greater electronegativity. Easily broken down in water. |
|
Hydrogen Bond |
a weak chemical attraction between a partial positively charged Hydrogen atom of one molecule and a partial negatively charged atom of another polar molecule. |
|
Properties of Hydrogen Bonds |
1. Easily broken. 2. Large numbers within a molecule add great stability. |
|
van der Waals Forces |
temporary, weak attractive forces which form between molecules. |
|
Free Radical |
molecule that has an atom with a single, unpaired electron in its outer shell. Steals electrons from other molecules and creates a new free radical. |
|
How Free Radicals Form |
1. Exposure to radiation or toxins 2. Response to disease-causing agents (in animals) |
|
Chemical Reaction |
when one or more substances are changed into other substances. |
|
Dehydration |
- removal of water - joins 2 molecules |
|
Hydrolysis |
- addition of water to break molecule(s) apart. |
|
High Heat of Vaporization |
x5 as much energy is needed to vaporize water than to raise it from O degrees Celsius to 100 degrees Celsius. |
|
High Specific Heat |
the amount of heat energy that must be lost to lower temperature by 1 degree Celsius. |
|
Surface Tension |
Measure of the attraction between molecules at the surface of a liquid. |
|
High Heat of Fusion |
melting. Results in the molecules within the substance becoming more chaotic
|
|
Colligative Properties |
properties that depend strictly on the total number of dissolved solutes, not on the specific type of solute. Boiling point; freezing point. |
|
Ice Floats |
ice floats because it's less dense than liquid water. |