Question

How many grams of hydrogen are there in one mole of sulphuric acid?

Answer 1

Hint:In order to calculate the amount of an element present in a molecule, in terms of grams, we need to know how many moles of that element is present in one mole of that molecule. We would then calculate the mass of that element present in the molecule by using the molar mass of that element.


Complete answer:
In order to answer this question, we need to know the molecular formula of sulphuric acid which is ${{H}_{2}}S{{O}_{4}}$. Now as we can see that the number of hydrogen atoms is two, in one molecule of sulphuric acid. This means that every mole of sulphuric acid contains two moles of hydrogen. The equation of dissociation of sulphuric acid into its ions can be chemically expressed as,
${{H}_{2}}S{{O}_{4}}\rightleftharpoons 2{{H}^{+}}+S{{O}_{4}}^{2-}$
We can see that two ions of hydrogen are liberated from one molecule of the sulphuric acid.
Now, we know that the molar mass of sulphuric acid is \[~98.0795{ }g/mol\], meaning the weight of every mole of sulphuric acid is \[~98.0795{ g}\].
Now, if we consider the question, it is being specified that we only need to know the grams of hydrogen in one mole of sulphuric acid, so, it is safe to say that there would be only two moles of hydrogen. Now, we will calculate the mass of two moles of hydrogen, by taking the molar mass of hydrogen.
$2molesH\times \dfrac{1.00794g}{1molAcid}=2.016gH$
Here, we took two moles of hydrogen, the molar mass of hydrogen as $1.00794g$ and per unit mole of sulphuric acid in order to find out the amount of hydrogen in grams.

Now, after rounding off this value we will get $2g$ as the amount of hydrogen present in one mole of sulphuric acid, which is the required answer.

Note:One mole of sulphuric acid contains two moles of hydrogen, as per the chemical formula of the sulphuric acid. We get approximately $2g$ of hydrogen per mole of sulphuric acid. The sulphuric acid is also termed as a diprotic acid because it contains two protons, which could be released very easily in aqueous solution.