Chemistry Study Guide

Protons

Have a positive charge and determine the identity of the element

Neutrons

have no charge and contributes to the atoms mass

Electrons

Have a negative charge and determines the charge of the ion

Atomic number

tells you the number of protons

How to find the mass number?

Total number of protons and neutrons

Neutral atoms have?

Same number of protons and electrons

Isotopes

atoms of the same element that have the same number of protons but different number of neutrons

Ions

Form when atoms gain or lose electrons

Cation

Lost electrons

Anions

Gain Electrons

How to find neutrons?

mass # - atomic #

How to find electrons?

atomic # - charge

Molar Mass

Mass of one mole of a substance

How to find molar mass?

Determine the atomic mass of substance, multiply it by the amount of substance in the equation

Atoms

single elements for example: C,Zn, Ne

Molecules

Particle with multiple atoms for example: H2, H20

Ionic “formula units”

Metal and nonmetal for example: NaCl, MgO

What is a mole?

1 mole = 6.02 × 10^ 23

Avogadros number

6.02 X 10^ 23

How to convert grams into moles?

Find the molar mass of compound, convert grams into moles with molar mass.

How to convert grams into atoms?

Convert grams into moles using molar mass, then use Avogadros number to convert moles into atoms