Answer:
a) boiling pressure:
P = 0.759 atm
b) mole fractions in the vapor phase:
Xethanol(v) = 0.2192
Xwater(v) = 0.7808
Explanation:
Raoult's law:
- Pa = (P*a)×(Xa,(l))
- Xa(l) + Xb(l) = 1
∴ a: water
∴ b: ethanol
∴ Xb(l) = 0.1238
⇒ Xa(l) = 1 - 0.1238 = 0.8762
vapor pressure of the pure components at T = 85.3°C:
∴ P*a(85.3°C) ≅ 400 torr (0.53 atm).....from literature
∴ P*b(85.3°C) ≅ 800 torr (1.053 atm).....from literature
total pressure of the mix:
⇒ Pt = ((0.53 atm)(0.8762)) + ((1.053 atm)(0.1238))
⇒ Pt = 0.5947 atm
boiling point:
- Xb(l) = Xa(l) = 0.5
- P = (P*b - Pt)(0.5) + P*a
⇒ P = ((1.053 atm - 0.5947 atm)(0.5)) + 0.53 atm
⇒ P = 0.759 atm
assuming that the gas system is ideal:
- (Xb(v))(Pt) = (P*b)(Xb(l))
fraction in the vapor fase, ethanol:
⇒ Xb(v) = (P*b)(Xb(l)) / Pt
⇒ Xb(v) = ((1.053 atm)(0.1238)) / (0.5947 atm)
⇒ Xb(v) = 0.2192
∴ Xa(v) = 1 - Xb(v)
⇒ Xa(v) = 1 - 0.2192 = 0.7808
When the use of significant figures and rounding up is applied correctly the mass of the mixture will be 80.5 g.
In cases of addition or subtraction, only the last significant figure of every number is taken into account.
In 30.05, this is 5, in the hundredths. When we look at 50.0, the last significant figure is 0, and it is in the tenths. And in 0.4006, the last significant figure is 6, in the ten thousandths. Of these three, the 0 from 50.0 is in the leftmost position, which means that the last significant figure of the result needs to be in the same position (in the tenths).
Moving onto the actual algebraic operation:
30.05 g + 50.0 g + 0.4006 = 80.4506 g
As we established, the last significant figure should be in the tenths, and we will have to round up 4 to 5 (trailing numbers are greater than 0), which means that the resulting mass will be 80.5 g.
You can learn more about significant figures here:
brainly.com/question/14804345
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In a chemical reaction, the mass of the products<span> is less than the mass of the reactants.
the first step in most stoichiometry problems is to <span>convert given quantities to moles.
Hope this helps! If it did, pls marky me brainly thank, and 5star me</span>
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Answer:
Minera and Aragonite
Explanation:
Limestone is a common type of carbonate sedimentary rock. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO 3). Limestone forms when these minerals precipitate out of water containing dissolved calcium.
They are totally different the Inner core is solid and hotter is made of iron, the outer core is liquid the and is made of iron and nickel
