In speech, we use alternative units to describe amounts of items. For instance, [latex]1[/latex] dozen [latex]=12[/latex] objects, [latex]1[/latex] score [latex]=20[/latex] objects, [latex]1[/latex] ream [latex]=500[/latex] sheets paper, likewise in chemistry, chemist consider: 
[latex]1~\textrm{mole}=6.022\times10^{23}\textrm{objects}[/latex]

The objects can be anything, such as houses, sand, eggs, oranges, etc. However, in chemistry, the objects we are concerned with are mainly atoms, ions or molecules – objects that are invisible to the naked eye!

One mole of anything contains [latex]6.022\times10^{23}[/latex] objects. For instance, one mole of eggs contains [latex]6.022\times10^{23}[/latex] eggs, one mole of carbon contains [latex]6.022\times10^{23}[/latex] carbon atoms, and one mole of carbon dioxide contains [latex]6.022\times10^{23}[/latex] carbon dioxide molecules.

The symbol of moles is “[latex]mol[/latex]”^[1].

• Thus, three moles (3 mol) of particles is three times [latex]6.022\times10^{23}[/latex] particles [latex]\left(3\times6.022\times10^{23}\right)[/latex], and ten moles (10 mol) of particles is ten times [latex]6.022\times10^{23}[/latex] particles [latex]\left(10\times6.022\times10^{23}\right)[/latex].
• If we had [latex]3.011\times10^{24}[/latex] atoms of gold [latex]\left(\ce{Au}\right)[/latex], the number of moles of gold would be: [latex]\ce{n(Au)}=\frac{3.011\times10^{24}\textrm{atoms}}{6.022\times10^{23}\textrm{atoms mole}^{-1}}=5.000\textrm{mol}[/latex]