# Isotopes – Examples, PDF

Some elements have different forms when scientists find them in nature or through scientific manufacturing. Researchers have categorized some forms of these elements into a category called isotopes.

## What Are Isotopes?

Isotopes are a category of a family of elements that all share the same amount of protons but have different numbers of neutrons or energy. Elements that can have isotopes will basically have different stable and unstable forms that their subatomic particles and structure will affect.

## How to Calculate Average Atomic Mass Using Isotopic Mass

Atomic mass is the overall amount of atomic matter inside a specific atom of an element. The average atomic mass uses the mass of the isotopes and the abundance of said isotopes of a specific element.

### Step 1: Obtain the Formula for Average Atomic Mass

Begin by obtaining the formula for atomic mass, which will act as the outline format for the whole equation. The formula for atomic mass is Average Atomic Mass = (Mass of Isotope 1 x Fractional Abundance of Isotope 1) + (Mass of Isotope 2 x Fractional Abundance of Isotope 2), you may extend the formula to accommodate more isotopes.

### Step 2 Obtain the Given Values

After obtaining the formula for atomic mass, you must obtain the values the question provides. Be sure that the values for the isotopes are using the correct form of measurement, which is an atomic mass unit or amu. If the measurement is wrong, convert the values accordingly.

### Step 3: Substitute the Values for the Correct Variables

After you have obtained the given values and have ensured that it is using the correct measurements, you must now substitute them for the correct variables in the formula. Doing this will help detail the various steps you will undergo to solve the overall equation.

### Step 4: Solve the Equation

When you have finished substituting all the values in the formula, you will have a working equation you can use to obtain the atomic weight. Solve the equation, which will give you an answer that will be measured in amu. If the question is asking for a different measurement, be sure to convert the answer to the desired measurement.