A sample contains 3.01 x 1023 molecules of SFn and its mass is 54 g. What is the value of n?
Answers
First of all, we can calculate the no. of moles in the sample as we have the no. of molecules.
We know, 1 mole contains 6.023 ×10^23 molecules (Avogadro's No. of molecules)
Thus 3.01×10^20 molecules will constitute 5×10^-4 moles.
We are given that this sample which is 5×10^-4 moles weighs 53mg or 5.3 ×10^-2 grams. By this information, we can find out the weight of one mole of the compound SFn which comes out to be
(5.3×10^-2) ÷(5×10^-4) = 1.06×10^2= 106 grams.
This is the molar mass or the mass of 1 mole of the compound.
The molar mass must be equal to the sum of gram atomic masses of the constituent atoms. We know that gram atomic mass of Sulphur is 32 and that of Flourine is 19. Therefore, we can say that
106=32×1+n×19.
On solving n comes out to be 3.894.
The answer is non integral because the sample is not a pure sample of exactly one compound. Like it might be mixture two or more sulphur and Flourine containing compounds.
Answer:0.5
Explanation: