Question

How many atoms are represented in 5.78 moles of ${{C}_{6}}{{H}_{12}}{{O}_{6}}$ glucose?

Answer 1

Moles is defined as the method of expressing the amount of the substance. The mole is generally defined as the amount of substance which contains the $6.023\times {{10}^{23}}$ elementary entities of the substance given. This $6.023\times {{10}^{23}}$ is known as Avogadro number.

Complete step by step solution:
The 1 mole of substance is also defined as the amount of substance which contains the same amount of particles present in 12g of carbon 12 atom.
Now the one mole of glucose contains 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms so in total it contains 24 atoms. That is,
1 mole of glucose contains = 24 atoms so,
5.78 moles of glucose contains = $24\times 5.78$
Now we know,
1mole of the substance contains= $6.023\times {{10}^{23}}$ atoms(Avogadro number)so,
$24\times 5.78$ of substance contains = $24\times 5.78\times 6.023\times {{10}^{23}}$
= $8.35\times {{10}^{25}}$atoms.
So the atoms represented in 5.78 moles of glucose is equal to $8.35\times {{10}^{25}}$ atoms.
The other conversion which are used in the moles concept are the following:
1g of the substance contains = $6.023\times {{10}^{23}}$ elementary entities.
22.4L of the substance contains = $6.023\times {{10}^{23}}$ elementary entities.
1 mole of the substance contains =$6.023\times {{10}^{23}}$ elementary entities.

Note: If the question asked you to find the volume which contains the certain amount of moles then you need to multiply the number of moles by 22.4L. if they asked to convert the moles in grams then you need to multiply the moles by their molecular weight. Always remember that the 1mole of compound or any substance contains the $6.023\times {{10}^{23}}$ molecules, atoms in it.