Polyacrylamide is used in manufacturing soft contact lenses. It consist of 50.69% carbon, 19.71% nitrogen, 7.09% hydrogen, and 22.51% oxygen. Calculate the empirical formula for polyacrylamide.

The empirical formula is .

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of C = 50.69 g

Mass of N= 19.71 g

Mass of H = 7.09 g

Mass of O = 22.51 g

Step 1 : convert given masses into moles.

Moles of C =

Moles of N=

Moles of H=

Moles of O =

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C =

For N =

For H =

For O =

The ratio of C:N:H: O = 3:1:5:1

Hence the empirical formula is .

the answer is 75.0%.