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:104.6cm^3
Explanation:
V of a cylinder =πr2h
V = pi((1.045cm)^2)(30.48)
V = 104.57cm^3
Explanation:
Energy required to raise the temperature from 35°C - 45 °C= 25116 J.
specific heat, the quantity of warmth required to raise the temperature of one gram of a substance by means of one Celsius degree. The units of precise warmth are generally energy or joules consistent with gram according to Celsius diploma. for instance, the unique warmth of water is 1 calorie (or 4.186 joules) according to gram in step with Celsius degree.
solving,
Sample of liquid = 400. 0 g
temperature = 30. 0 ºc
joules of energy are required to raise the temperature of the water to 45. 0 ºc
therefore rise in temperature 45 - 30 = 15°C
Specific heat capacity = 4.186 J/g m °C
In kelvin = 273 + 15 = 288
= ∴ energy required = Q = m s ( t final - t initial)
= 400*4.186 * 15
= 25116 joule
Learn more about specific heat here:-brainly.com/question/21406849
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Answer:
D, because he discovered electrons
Explanation:
Answer: 0.5 mole Mg
Explanation: solution:
12 g Mg x 1 mole Mg / 24 g Mg
= 0.5 mole Mg