Science Project

By: Adrian Allotey

Elements and Compounds

Elements are substance that can't be separated into simpler substances.

Compounds are 2 or more elements combined.

Hydrogen is an element and water is a compound.

Element properties disappear when they form into a compound because the element changes into a completely different substance. The properties of an element are different from the properties of an atom because another element is chemically combined with another element. If a compound was to separate back into element, all of of the elements would get their properties back.
Compounds are formed when two or more elements are chemically combined. If they are physically combined, they will not make a compound. can only be separated chemically. To separate a compound you must separate the bonds of the atoms. There are many different ways of doing this. Unlike compounds elements can not not be separated because they are already in their simplest substance.
Some similarities between compounds and elements are that they are both made out of atoms, elements and and made of matter.

Some differences between the two are that an element has only one one exact atom , but a compound has two or more different atoms, compounds can be separated into simpler substances by chemical means but elements can't, and elements are shown on the periodic table, but compounds are not.

Chemical Formulas

A chemical formula is a way to show the number and type of atoms in a compound and the number of atoms in an element.

Coefficients and Subscripts

Coefficients are the big numbers to the left of a symbol in a chemical formula.

-They tell you how much of the the rest of he formula should be multiplied by

Subscripts are the small numbers to the right of a symbol in a chemical formula

-They tell you how many times the element is used.

There are several steps to counting how many elements and atoms in a formula. To find the number of molecules in a chemical formula you must add all of the coefficients. Remember that if there is no coefficient number, there is only one.To find the number of elements count the number of capitalized letters.