Avogradro's Number [ENDORSED]

[Claire Lo 3C]

So I was doing E5 on the textbook and it asks how many moles of people inhabit Earth if the estimated population is 7.0 billion people. This made me question the definition of 1 mole and Avogadro's number.

[Alan Wu]

1 mole just means 6.022 * 10^23 number of things. It is just like how you would say I have a dozen eggs, where dozen refers to "12". You can have 1 mole of atoms, 1 mole of eggs, or in this case, 1 mole of humans. For this question, to find how many moles of humans there are on Earth, simply divide 7.0 billion by 6.022 * 10^23 and you get 1.2 * 10^-14 moles of humans.

[sarahforman_Dis2I]

I think what this question is getting at is just how large the unit of a "mole" is. Even though it seems strange to think that the world does not even have close to one mole of people, this unit is useful when used in the context of atoms, as a mole of atoms can be held in your hand. Since Avogadro's number is so large, it is a useful unit in quantifying very small particles, such as atoms and molecules.

[Jialun Chen 4F]

Try to think 1 mole as 1 dozen. Just as one dozen refers to 12 of some object, 1 mole refers to 6.022*10^23 of something. Avogadro's number is simply 6.022*10^23. Hope this can help.

[Micah3J]

Why is Avogradro's number based on Carbon 12?

[Justin Quan 4I]

Why is Avogradro's number based on Carbon 12?

Chemists chose to use Carbon 12 because Carbon 12 has 6 protons, 6 neutrons, and 6 electrons.This is interesting because the mass of an electron is about 1/12th the mass of Carbon 12. Chemists also found that when you have Avogadro's number of Carbon 12, you will have exactly 12grams worth of Carbon 12.