6.5ABC Elements and Compounds
Atmosphere
A mixture of mainly nitrogen and oxygen, with small amounts of other gases that surround Earth
Element
A pure substance that cannot be separated into simpler substances by physical or chemical means
Chemical Formula
A shorthand notation that uses chemical symbols and numbers as subscripts to represent the type of atoms and number of atoms that are present in the smallest unit of the substance
Periodic Table of Elements
An arrangement of the elements according to their atomic numbers and periodic trends of physical and chemical properties
Matter
Anything that has volume and mass
Living Matter
Cells from living matter are made of carbon bonded to other elements, such as hydrogen, oxygen, phosphorus, nitrogen, calcium, or sulfur
Compound
Matter that is composed of two or more elements that are chemically combined
Pure Substance
Matter that is made up of the same particles throughout
Solid Earth
Oxygen and silicon are the main elements of matter that make up the rock and minerals of Earth's crust
Periods
The horizontal rows in a periodic table that classify the elements by select characteristics
Atomic Number
The number of protons (positive charges) in an atomic nucleus
Chemical Reaction
The process by which one or more substances change to produce one or more different substances
Atom
The smallest unit of an element that has all of the properties of that element
Chemical Symbol
The symbol that represents each element on the periodic table
Groups
The vertical columns on a periodic table that arrange the elements by select characteristics
Physical Property
Those characteristics that can be observed without changing the identity of the substance such as size, shape, luster, conductivity, malleability, and magnetic attraction
Oceans
Water is made up of the elements hydrogen and oxygen