Answer:
Explanation:
The vapor pressure of diethyl ether (ether) is 463.57 mm Hg at 25 °C. A nonvolatile, nonelectrolyte that dissolves in diethyl ether is aspirin. Calculate the vapor pressure of the solution at 25 °C when 14.88 grams of aspirin, C9H8O4 (180.1 g/mol), are dissolved in 269.2 grams of diethyl ether. diethyl ether = CH3CH2OCH2CH3 = 74.12 g/mol.
mol of C4H10O = mass of C4H10O / molar mass of C4H10O
= 242.1 g / 74.12 g/mol
= 3.266 mol
mol of C9H8O4 = mass of C9H8O4 / molar mass of C9H8O4
= 10.33 g / 180.1 g/mol
= 0.05736 mol
mole fraction of C4H10O,
X = mole of CHH1O0 / total mol
= (3.266)/(3.266 + 0.05736)
= 0.9827
now use:
P = Po*X
P = 463.57 * 0.9827
= 455.6 mm Hg
Helium can be liquefy through a very
low temperature because of the weakness of attractions between the helium
atoms. In addition, helium is a noble gas that has a very weak interatomic London
dispersion forces. Thus, this element would remain liquid at atmospheric pressure
all the way to its liquefaction point going to absolute zero.
<span> </span>
Answer:233 Joules/K
Explanation:
∆H= 26.5KJmol-1
Kelvin temperature = 34.6 + 273 = 307.6 K
No of moles= 2.7 moles
2.70 mole x 26.5 kJ/mole = 71.55kilojoules
∆S=71.55 kilojoules / 307.6 K = 0.233 kilojoules/ K
Convert to JK-1
0.233 kilojoules/ K x 1000 Joules/kilojoule = 233 Joules/K
Answer:
Explanation:
Atomic mass of element will be weighted average atomic mass of the element
= 89.90470 x 0 .5293 + 90.90565 x. 1154 + 91.90504 x 0. 1765 + 93.90632 x 0.1788
= 47.58955 + 10.490 + 16.2212 + 16.790
= 91.10 u .
