To determine the mass of xenon tetrafluoride, we need to know first the number of fluorine atoms present in <span>oxygen difluoride. We need to convert first the mass into moles then make use of the relation of the elements from the chemical formula. Then, use the avogadro's number to convert it to number of atoms. Then, we do the reverse of the steps above but this time for </span><span>xenon tetrafluoride.
25.0 g OF2 ( 1 mol / 54 g ) ( 2 mol F / 1 mol OF2 ) ( 6.022 x10^23 atoms F / 1 mol F ) ( 1 mol / 6.022x10^23 atoms) ( 1 mol XeF4 / 4 mol F ) (207.3 g / 1 mol XeF4) = 47.99 g XeF4</span>
Answer: 3.5 moles
Explanation:
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 molecules
So, 1 mole of SiO4 = 6.02 x 10^23 molecules
Zmoles of SiO4 = 2.1 x 10^{24} molecules
To get the value of Z, cross multiply:
(2.1 x 10^{24} molecules x 1mole) = (6.02 x 10^23 molecules x Z moles)
2.1 x 10^{24} molecules = (6.02 x 10^23 x Z)
Z = (2.1 x 10^{24}) ➗ (6.02 x 10^23)
Z = 3.5 moles
Thus, there are 3.5 moles of SiO4.
We need to know the value of van't hoff factor.
The van't hoff factor is: 2.66 or 2.7 (approximately)
(NH₄)₂SO₄ is an ionic compound, so it dissociates in solution and produces 3 ionic species. Therefore van't hoff factor is more than one.
From the equation: Δ
=i 
.m, where Δ= elevation of boiling point=102.5 - 100=2.5°C.
m=molality of solute=1.83 m (Given)
= Ebullioscopic constant or Boiling point elevation constant= 0.512°C/m (Given)
i= Van't Hoff factor
So, 2.5= i X 0.512 X 1.83
i=
i=2.66= 2.7 (approx.)
