There are a number of steps involved in determining the empirical formula of a c

Question

There are a number of steps involved in determining the empirical formula of a compound. You will need to demonstrate that you can complete all of these steps as you determine the empirical formula of a compound composed of phosphorus and chlorine that is 14.87 % P by mass. Complete your calculations based on 100 g of this compound. Enter all calculated values in 4 significant figures followed by one space and the appropriate unit. Use g for grams and mole for moles. Do not use scientific notation.

Determine the mass in grams of chlorine present in the sample. Answer

Determine the number of moles of phosphorus in the sample. Answer

Determine the number of moles of chlorine in the sample.
Answer

The moles of (Answer Cl or P) represents the smaller mole value.

Write the empirical formula of the compound. You will not be able to show subscript values correctly. For example, H2O would be recorded for water.
Answer

Explanation / Answer

14.87 % by mass means in 100 g of sample

Weight of P (phosphorous) = 14.87 g

weight of Cl (chlorine) = 85.13 g

No of moles of P = given wt./ molecular mass = 14.87/30.97 = 0.4801 mole

No of moles of Cl = given wt./ molecular mass = 85.13/35.45 = 2.401 moles

No of moles of (Phosphorous) P is smaller than Cl , therefore

Simplest ratio

For P = 0.4801/0.4801 = 1

For Cl =2.401/0.4801 = 5

So the empirical formula becomes = PCl5

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