The correct answer would be the last option. A double displacement type of reaction involves the switching of places the cations and anions accordingly. The given reaction is erroneous since in the product side the anions and cations are being paired which would not make sense. The correct reaction should be
4NaBr + Co(SO3)2 yields <span>CoBr4 + 2Na2SO3</span>
Chris is correct because the reactants and products do not have to have the same mass, but they do have to weigh the same. Is the correct answer:) Hannah is right because the mass of the reactants was different than the mass of the products. is incorrect
- The mass percent of
Pentane in solution is 16.49%
- The mass percent of
Hexane in solution is 83.51%
<u>Explanation</u>:
- Take 1 kg basis for the vapor: 35.5 mass% pentane = 355 g pentane with 645 g hexane.
-
Convert these values to mol% using their molecular weights:
Pentane: Mp = 72.15 g/mol -> 355g/72.15 g/mol = 4.92mol
Hexane: Mh = 86.18 g/mol -> 645g/86.18 g/mol = 7.48mol
Pentane mol%: yp = 4.92/(4.92+7.48) = 39.68%
Hexane mol%: yh = 100 - 39.68 = 60.32%
Pp-vap = 425 torr = 0.555atm
Ph-vap = 151 torr = 0.199atm
-
From Raoult's law we know:
Pp = xp
Pp - vap = yp
Pt (1)
Ph = xh
Ph - vap = yh
Pt (2)
-
Since it is a binary mixture we can write xh = (1 - xp) and yh = (1 - yp), therefore (2) becomes:
(1 - xp)
Ph - vap = (1 - yp)
Pt (3)
-
Substituting (1) into (3) we get:
(1-xp)
Ph - vap = (1 - yp)
xp
Pp - vap / yp (4)
xp = Ph - vap / (Pp - vap/yp - Pp - vap + Ph - vap) (5)
-
Subbing in the values we find:
Pentane mol% in solution: xp = 19.08%
Hexane mol% in solution: xh = 80.92%
-
Now for converting these mol% to mass%, take 1 mol basis for the solution and multiplying it by molar mass:
mp = 0.1908 mol
72.15 g/mol
= 13.766 g
mh = 0.8092 mol
86.18 g/mol
= 69.737 g
-
Mass% of Pentane solution = 13.766/(13.766+69.737)
= 16.49%
-
Mass% of Hexane solution = 83.51%
This would be the Melting point because it is showing that at a certain heat it melts so therefore it is the point it melts and therefore called the melting point