A mole of a pure substance contains 6.02x10^23 atoms. Alway true, sometime true or never true?
-I was thinking sometime true since a pure substance can be like H2O but H2O have 3 "atoms" (Is this what you call individual part of H2O?). Each "atoms" have 6.02E23 so it wouldn't be 6.02E23 atoms. Thanks
Sometimes true.
It is always true that a mole of any pure substance contains 6.02x10^23 entities. However, the number of atoms in a mole of a specific substance can vary depending on the atomic composition. For example, in one mole of water (H2O), there would be 6.02x10^23 water molecules, but a water molecule consists of three atoms (two hydrogen atoms and one oxygen atom), so there would be a total of 3 times 6.02x10^23 atoms in one mole of water.
The statement "A mole of a pure substance contains 6.02x10^23 atoms" is always true.
In chemistry, a mole is a unit used to express the amount of a substance. It represents Avogadro's number, which is approximately 6.02x10^23. This number is defined as the number of particles (atoms, molecules, or ions) present in one mole of a substance.
When we say that a mole of a pure substance contains 6.02x10^23 atoms, we mean that one mole of any pure substance will contain this specific number of atoms. It doesn't matter if the substance is H2O or any other compound. For example, one mole of H2O contains 6.02x10^23 water molecules, and since each water molecule consists of three atoms (two hydrogen atoms and one oxygen atom), there will be a total of 6.02x10^23 atoms in one mole of water.
So, to answer your question, the statement "A mole of a pure substance contains 6.02x10^23 atoms" is always true, regardless of the specific composition of the substance.