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Answer:
A
Explanation:
Molecules of a gas are relatively more compressible than those of liquids and solids because they are relatively far apart without any intermolecular forces between them. However, at lower temperature and higher pressure, there is now a significant intermolecular interaction between the gas molecules and they are no longer relatively far apart. Hence they are more compressible than liquids and solids which already possess significant intermolecular interaction and thus a definite volume.
Answer: It will be produced 276,3 mg of product
Explanation: The reaction of anthracene (C14H10) and maleic anhydride (C4H2O3) produce a compound named 9,10-dihydroanthracene-9,10-α,β-succinic anhydride (C18H12O3), as described below:
C14H10 + C4H2O3 → C18H12O3
The reaction is already balanced, which means to produce 1 mol of C18H12O3 is necessary 1 mol of anthracene and 1 mol of maleic anhydride.
1 mol of C14H10 equals 178,23 g. As it is used 180 mg of that reagent, we have 0,001 mol of anthracene. With it, the reaction produces 0,001 mol of C18H12O3.
As 1 mol of C18H12O3 equals 276,3 g, the mass produced is 276,3 mg.
- 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%
The words aa q.s. is an abbreviation which is used in
pharmacy. This is usually written by prescribers and then translated by
pharmacists. The aa is derived from Latin which means “of each” while q.s. is
also derived from Latin which means “a sufficient quantity”. This simply means
that there is equal amount of Hytone 1% cream and Lotrimin 1% cream in the
total cream formulation.
Since we are to make a total of 60 g of cream, therefore
50% of it would be Lotrimin cream.
Amount of Lotrimin cream needed = 0.5 (60 g)
<span>Amount of Lotrimin cream needed = 30 grams</span>
