Answer:
P = 2.92 atm
Explanation:
With the three assumptions in mind, the system consists of:
- A liquid phase containing n-hexane and n-heptane, and
- A gaseous phase containing n-hexane vapor, n-heptane vapor, and nitrogen gas.
First we use PV=nRT to calculate the moles of n-hexane and n-heptane in the gaseous phase:
P = 0.199 MPa ⇒ 0.199 * 1.869 = 1.964 atm
- 1.964 atm * 648 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 365 K
P = 0.083 MPa ⇒ 0.083 * 1.869 = 0.155 atm
- 0.155 atm * 648 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 365 K
So <u>the gaseous phase consists of 42.52 moles of n-hexane, 3.358 moles of n-heptane, and 14 mol of nitrogen</u>.
For the liquid phase, we <u>calculate the remaining moles of n-hexane and n-heptane</u>. Then we<u> convert to liters</u>, using their molar volumes:
- n = 112 mol - 42.52 mol = 69.48 mol
- 69.48 mol * 0.146 L/mol = 10.14 L
- n = 155 mol - 3.358 mol = 151.642 mol
- 151.642 mol * 0.162 L/mol = 24.57 L
So the liquid phase occupies (10.14+24.57) = 34.71 L, and <u>contains 69.48 mol of n-hexane and 151.64 mol of n-heptane</u>.
Finally, to<u> calculate the pressure in the vessel</u>, we use PV=nRT:
P = ?
V = 648 - 34.71 = 613.29 L
n = 42.52 mol hexane + 3.35 mol heptane + 14 mol nitrogen = 59.87 mol
T = 365 K
- P * 613.29 L = 59.87 mol * 0.082 atm·L·mol⁻¹·K⁻¹ * 365 K
There are zero lone pairs of electrons on the central carbon atom in a Lewis Structure of CHI3. The correct option is b.
Explanation:
Lone pair electrons are those valence electrons of an atom which do not take part in bonding or left after the bonds are formed.
CH
carbon is the central atom in the compound having 4 valence electrons.
Each iodine molecule has 7 valence electrons.
H has 1 valence electron.
from the Lewis structure of CH
, it is seen that all four valence electrons of the carbon is involved in bonding with 3 atoms of iodine and 1 atom of hydrogen.
Thus when all valence electrons are involved in bonding no lone pair of electron is found in CH
that means zero lone pairs of electrons.
The octet of the iodine, carbon and hydrogen gets completed to form the compound.
If the humidity of the room is low, the water that contacts the air directly could evaporate and takes some energy from the bulk thus decreasing its temperature steadily. This allows the water to have a lower temperature.