All about Elements and Compounds
Element
An element is a pure substance that can't be seperated into a simpler substance.
-Example: Aluminum
Compound
A compound is two or more elements chemically combined.
-Example: Salt
Compounds
Similarities & Differences between Elements and Compounds
Elements are a substance in its simplest form, they can't be broken down by either chemical or physical means. (ex. Sodium, Na)
Compounds are substances composed of two or more elements chemically combined together. They can't be broken down by physical means, but can be broken down through chemical reactions. They both are pure substances. Compounds have two or more differnt types of atoms, while elements are pure substances that have the exact same type of atom.
Chemical Formulas
A chemical formula of a substance is a notation that uses atomic symbols with numerical subscripts to convey the relative proportions of atoms of each element in that substance. In a chemical formula, the chemical symbol of each element is shown with subscript numbers which tell us the numbers or ratio of atoms in the compound or molecule element.
-Example: H2O=water
Element Properties
Coefficient and Subsripts
Coefficients are numbers used to multiply a variable. A number or symbol multiplied with a variable or an unknown quanitity.
-Example: 2H2 + O2 ---- 2H2O (The two's at the very front. before the H's both times.)
Subscripts are a distinguishing symbol as a letter or numeral written immediately below or below and to the right or left of another character.
-Example: CO-----CO2
How to count Elemements and Atoms in a Chemical Formula
To count atoms, use the subscript to find how many of each type of atom there is. If a coefficient is present, multiply the subscript and coeffiecient to find the total amount of atoms for that given element.
-Example: 9H2O=19 atoms
The chemical formula identifies each element by its chemical symbol and indicates the number of atoms of each element found in each molecule of that compound. If a molecule has more than one atom of a particular element, thee quantity is indicated using a subscript after the chemical symbol and also can be combined by more chemical elements.
-Example: Carbon, Hydrogen, and Oxygen = C6H12O6