Question

How can I find the mole ratio of anhydrous salt to water?

Answer 1

Moles are defined as the basic unit or the smallest unit which is used in measuring the large number of the atoms, molecules or ions. The 1 mole is defined as the amount of substance present in the $\frac{1}{12}$th part of the carbon 12 atom. The 1 mole of the substance is equal to Avogadro number.

Complete step-by-step answer: To find the mole ratio of the anhydrous salt to water firstly we should calculate the mass of the hydrated salt. Let the mass of the hydrated salt be ${{m}_{1}}$. Now let us calculate the mass of the salt after it has lost its water and get dried. Let us take this mass of anhydrous salt be ${{m}_{2}}$.now the mass of water should be taken as ${{m}_{w}}$. So now let us calculate the mass of water by subtracting the mass of hydrated salt from anhydrous salt. And take the mass of water as ${{m}_{w}}$.now we need to convert the calculated mass of water into moles by just dividing the mass of water by the molar mass of the water that is $18.02gmo{{l}^{-1}}$. Now we need to convert the calculated mass of the anhydrous salt into the moles by dividing it by the molar mass of the anhydrous salt.
Now we will have the moles of anhydrous salt and the moles of water. so out of them the moles of salt would be less. Now divide the moles of the water by the moles of the anhydrous salt so that we get the mole ratio. Like this the mole ratio will be calculated.

Note: If we need to calculate the number of moles through the volume of the substance then we need to divide the given volume by 22.4L. this is so because 1 mole of the substance is equal to 22.4L. if we need to calculate the number of ions in the substance then multiply the moles of substance by the Avogadro number.