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How many atoms are<br>in the human body?

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in the human body?)

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How many atoms would<br>it take to create a ton?

How many atoms are there in the world?

The quick answer is: more than you can count! But we can get an estimate of the number of atoms in the earth by first knowing what its mass is. The mass of an object is a measure of how much material the object has. The mass of the earth is 5.98*1027 grams. That's the scientific way to write a large number that has a lot of zeros. We can write the mass of the earth with all the zeros like this:

5,980,000,000,000,000,000,000,000,000 grams

Below is a table that shows the breakdown of the fractional amount of the earth for the most abundant types of atoms (also called the element). Some of these values are estimates since we really don't know exactly what the center of the earth is made of but scientists have pretty good theories about it. In the table is also a list of how many grams a mole of an element weighs. The bottom line is that there are about 1.33*1050 atoms in the world. If you want to write it with all the zeros it would be:

133,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

ElementGrams
per mole
Fraction
of the Earth
Amount in the
Earth in grams
Number
of atoms
Iron55.80.352.09*10272.26*1049
Oxygen16.00.301.79*10276.75*1049
Silicon28.10.158.97*10261.92*1049
Magnesium24.30.137.77*10261.93*1049
Sulfur32.10.021.20*10262.24*1048
Calcium40.10.015.98*10258.98*1047
Aluminum27.00.015.98*10251.33*1048
SUM1.33*1050

Author:

Drew Weisenberger, Detector Scientist