To get the answer you use the Law of Raoult.
Raoult's law states that the decrease of the vapor pressure of a liquid is proportional to the molar fraction of the solute.
ΔP = Pa * Xa
Here Pa = 0.038 atm
And Xa = N a / (Na + Nb), where Na is number of moles of A and Nb is number of moles of b
Na = mass of urea / molar mass of urea = 60 g / (molar mass of CH4N2O)
molar mass of CH4N2O = 12 g/mol + 4*1g/mol + 2*14 g/mol + 16 g/mol = 60 g/mol
Na = 60 g / 60 g/mol = 1 mol
Nb = mass of water / molar mass of water = 180g / 18g/mol = 10 mol
Xa = 1 mol / (10 mol + 1 mol) = 1/11 =0.09091
ΔP = Pb * Xa = 0.038 atm * 0.09091 = 0.0035 atm
Then, the final vapor pressure of water is Pb - ΔP = 0.038atm - 0.0035atm = 0.035 atm.
Answer: 0.035 atm
Answer:
HCl
Explanation:
<em>Choices:</em>
<em>CO: 28.01g/mol</em>
<em>NO₂: 46g/mol</em>
<em>CH₄: 16.04g/mol</em>
<em>HCl: 36.4g/mol</em>
<em>CO₂: 44.01g/mol</em>
<em />
It is possible to identify a substance finding its molar mass (That is, the ratio between its mass in grams and its moles). It is possible to find the moles of the gas using general ideal gas law:
PV = nRT
<em>Where P is pressure of gas 0.764atm; V its volume, 0.279L; n moles; R gas constant: 0.082atmL/molK and T its absolute temperature, 295.85K (22.7°C + 273.15).</em>
Replacing:
PV = nRT
PV / RT = n
0.764atm*0.279L / 0.082atmL/molKₓ295.85K = n
<em>8.786x10⁻³ = moles of the gas</em>
<em />
As the mass of the gas is 0.320g; its molar mass is:
0.320g / 8.786x10⁻³moles = 36.4 g/mol
Based in the group of answer choices, the identity of the gas is:
<h3>HCl</h3>
<em />
D. The particles are tightly packed together
The density of ice is less than the density of water (liquid). We generally observe that the density of a solid substance is more than its liquid form as volume of a solid is generally less than the liquid, However in case of water this is not true.
The volume of ice is less than that of liquid water due to an open cage like structure in ice which gives its a wide structure. This cage like structure is due to presence of hydrogen bond (more extensive) in ice.
The maximum density of water is observed at 4 degree celsius
Answer:
4.2 Liters (2 sig-figs)
Explanation:
Apply Boyles Law ... P₁V₁ = P₂V₂
P₁ = 712 Torr P₂ = 3560 Torr
V₁ = 21.0L V₂ = ?
P₁V₁ = P₂V₂ => V₂ = P₁V₁/P₂ = (712Torr)(21.0L)/(3560Torr) = 4.2 Liters (2 sig-figs)
