What amount of a substance is contained in 394 g of sulfuric acid H2SO4? How many molecules will there be in this amount?

In order to find the amount of a substance in a certain mass of acid, you must first determine the molar mass of the acid.

Let’s find the molar mass of sulfuric acid. To do this, we add up the molar masses of the atoms that enter the molecule.

M H2SO4 = 2 + 32 + 16 x 4 = 98 grams / mol;

Let’s find the amount of a substance by dividing the mass of a substance by its molar mass:

N H2SO4 = 394/98 = 4.02 mol;

One mole of a substance contains 6.022 x 10 ^ 23 molecules.

Find the number of molecules in 4.02 mol of sulfuric acid.

K H2SO4 = 6.022 x 4.02 x 10 ^ 23 = 24.21 x 10 ^ 23 = 2.421 x 10 ^ 24 molecules;