Reading...
Play button
Play button
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;
30 Cards in this Set
- Front
- Back
|
Continuous theory of matter
|
During the earliest years of scientific investigation, ancient Greek philosophers thought that the matter inside a substance was continuous. By this they meant that you could take any substance and divide it in half over and over again.
|
|
|
Discontinuous theory of matter
|
The idea that matter is, in fact, composed of tiny, individual particles. Our eyes simply cannot see these particles, so the apparent continuity of matter is, in fact, just an illusion.
|
|
|
The Law of Mass Conservation
|
Matter cannot be created or destroyed; it can only change forms.
|
|
|
Decomposition
|
There are some substances that can undergo change in such a way as to make many other substances, each less massive than the original.
|
|
|
Element
|
Any substance that cannot be decomposed into less massive substances.
The basic building blocks of all substances. Formed when compounds are broken down into their component parts. |
|
|
Periodic Table of Elements
|
compilation of the most important information concerning each element into a table
|
|
|
Metals
|
Elements that are usually malleable (can be easily bent and shaped), have luster (are shiny), and are able to conduct electricity.
|
|
|
Nonmetals
|
Typically brittle (break easily when you try to bend or shape them), lack luster, and do not conduct electricity.
|
|
|
Metalloids
|
These elements have some metal properties and some nonmetal properties.
|
|
|
Compounds
|
Substances that can be decomposed into elements by chemical means.
Compounds are formed when elements group together to form a new substance. |
|
|
The Law of Definite Proportions
|
The proportion of elements in any compound is always the same.
There is a single “recipe” that governs how much of each element is needed to make a particular compound. If you don't add elements together in exactly the proportion the recipe calls for, then there will be some “leftover” ingredients at the end. |
|
|
Dimensionless quantities
|
In solving an expression for "x"........ if the units cancel out, then x has no units...... making it a dimensionless quantity.
|
|
|
The Law of Multiple Proportions
|
If two elements combine to form different compounds, the ratio of masses of the second element that react with a fixed mass of the first element will be a simple, whole-number ratio.
This law says that sometimes you can find different ways of combining elements. (think: carbon dioxide versus carbon monoxide!) The whole number ratio for this would be: 32.0:16.0, or 2:1. |
|
|
Molecules
|
The groups that are formed when atoms join together to form compounds.
In other words, while all elements are composed of identical atoms, all compounds are composed of identical molecules. |
|
|
Compound
|
When a substance is made up of molecules, it is called this.
|
|
|
Chemical symbol
|
The term chemists use for the abbreviation for an atom.
Sometimes chemists drop the word “chemical” and simply use the terms “symbol” and “formula.” |
|
|
Chemical formula
|
Sometimes chemists drop the word “chemical” and simply use the terms “symbol” and “formula.”
|
|
|
Ionic compound
|
When dissolved in water, it conducts electricity.
(Remember, pure water does not conduct electricity) |
|
|
Covalent compound
|
A compound that does not allow water to conduct electricity after it is dissolved.
|
|
|
Distilled water
|
Distilled water is about 99% pure water.
|
|
|
mono
|
one
|
|
|
di
|
two
|
|
|
tri
|
three
|
|
|
tetra
|
four
|
|
|
penta
|
five
|
|
|
hexa
|
six
|
|
|
hepta
|
seven
|
|
|
octa
|
eight
|
|
|
nona
|
nine
|
|
|
deca
|
ten
|
