Answer:
-2.3 ºC
Explanation:
Kf (benzene) = 5.12 ° C kg mol – 1
1st - We calculate the moles of condensed gas using the ideal gas equation:
n = PV / (RT)
P = 748/760 = 0.984 atm
T = 270 + 273.15 = 543.15 K
V = 4 L
R = 0.082 atm.L / mol.K
n = (0.984atm * 4L) / (0.082atm.L / K.mol * 543.15K) = 0.088 mol
Then, you calculate the molality of the solution:
m = n / kg solvent
m = 0.088 mol / 0.058 kg = 1.52mol / kg
Then you calculate the decrease in freezing point (DT)
DT = m * Kf
DT = 1.52 * 5.12 = 7.8 ° C
Knowing that the freezing point of pure benzene is 5.5 ºC, we calculate the freezing point of the solution:
T = 5.5 - 7.8 = -2.3 ºC
Answer:
The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or "L shell"), then the "3 shell" (or "M shell"), and so on farther and farther from the nucleus.
The hydrogen one because who doesnt like snoballs'
Answer:
5 , I think. sorry if its wrong
Answer:
118750 ml
Explanation:
The chemical equation for complete combustion of hexane is given as;
2C6H14 + 19O2 → 12CO2 + 14H2O
From the equation of the reaction;
2 mol of C6H14 reacts with 19 mol of O2
2 ml of C6H14 reacts with 19 ml of O2
2500 mL of C6H14 would react with x ml of O2
2 = 19
2500 = x
x = 2500 * 19 / 2 = 23750 ml
Since oxygen is 20% of air;
23750 = 20 / 100 * (Volume of air)
Volume of air = 23750 * 100 / 20 = 118750 ml