Answer:
P=atm

Explanation:
The problem give you the Van Der Waals equation:

First we are going to solve for P:


Then you should know all the units of each term of the equation, that is:







where atm=atmosphere, L=litters, K=kelvin
Now, you should replace the units in the equation for each value:

Then you should multiply and eliminate the same units which they are dividing each other (Please see the photo below), so you have:

Then operate the fraction subtraction:
P=

And finally you can find the answer:
P=atm
Now solving for b:




Replacing units:

Multiplying and dividing units,(please see the second photo below), we have:



Answer:
The equilibrium will shift to the left to favor the reactants.
Explanation:
Remember that the reaction quotient (Qc) is derived from initial concentrations of reactants and products. Since Qc is greater than Kc, this means that initial concentrations are heavily impacted by a high product concentration ([HI]). Therefore, the reverse reaction will occur and actually create more reactants again ([H2] and [I2]). Thus, the answer is that the equilibrium will shift to the left side to favor the reactants.
Explanation:
Physical change -
It refers to any change during any process , where there is no new substance is formed , is referred to as a physical change.
Any change in the state of matter is characterised under physical change.
Chemical change -
It refers to any change in a chemical process , where there is formation of any new substance , is referred to as a chemical change .
From the options given in the question,
1. Apple turning brown , on air exposure , is an example of chemical change .
2. The physical state of mercury is liquid , is an example of physical change .
3. phosphorus burns on exposed to air , is an example of chemical change .
4. The gas Neon is colorless at the room temperature , is is an example of physical change .
Since there are 63.01284 grams to one mole of HNO3, then 12.5 moles would be in 450 grams of it.