Answer: The empirical formula is

Step-by-step 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 H= 2.270 g
Mass of P = 34.80 g
Mass of O = 62.93 g
Step 1 : convert given masses into moles
Moles of H =

Moles of P =

Moles of O =

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

For P=

For O =

The simples ratio will be = H: P : O= 4: 2: 7
Hence the empirical formula is
