The molecule is unstable and impossible to create the PCl_6
Only one way is that change the formula
Lets look at structure(See attachment)
There are total 7atoms
Answer:
Option A; V = 2.92 L
Explanation:
If we assume a lot of things, like:
The gas is an ideal gas.
The temperature is constant.
The gas does not interchange mass with the environment.
Then we have the relation:
P*V = n*R*T = constant.
Where:
P = pressure
V = volume
n = number of moles
R = constant of the ideal gas
T = temperature.
We know that when P = 0.55 atm, the volume is 5.31 L
Then:
(0.55 atm)*(5.31 L) = constant
Now, when the gas is at standard pressure ( P = 1 atm)
We still have the relation:
P*V = constant = (0.55 atm)*(5.31 L)
(1 atm)*V = (0.55 atm)*(5.31 L)
Now we only need to solve this for V.
V = (0.55 atm/ 1 atm)*(5.31 L) = 2.92 L
V = 2.92 L
Then the correct option is A.
Answer : The final temperature of the metal block is, 
Explanation :

As we know that,

.................(1)
where,
q = heat absorbed or released
= mass of aluminum = 55 g
= mass of water = 0.48 g
= final temperature = ?
= temperature of aluminum = 
= temperature of water = 
= specific heat of aluminum = 
= specific heat of water= 
Now put all the given values in equation (1), we get
![55g\times 0.900J/g^oC\times (T_{final}-25)^oC=-[0.48g\times 4.184J/g^oC\times (T_{final}-25)^oC]](https://tex.z-dn.net/?f=55g%5Ctimes%200.900J%2Fg%5EoC%5Ctimes%20%28T_%7Bfinal%7D-25%29%5EoC%3D-%5B0.48g%5Ctimes%204.184J%2Fg%5EoC%5Ctimes%20%28T_%7Bfinal%7D-25%29%5EoC%5D)

Thus, the final temperature of the metal block is, 
Answer:
B?
Explanation:
In the example, the amount of hydrogen is 202,650 x 0.025 / 293.15 x 8.314472 = 2.078 moles. Use the mass of the hydrogen gas to calculate the gas moles directly; divide the hydrogen weight by its molar mass of 2 g/mole. For example, 250 grams (g) of the hydrogen gas corresponds to 250 g / 2 g/mole = 125 moles.