Answer:
Hello, Your answer is <em>B) Making observations</em>
<u><em>(Hope That Helps Your Answer)</em></u>
Answer:
The final volume 
Explanation:
between work ( w), pressure ( P ) and volume ( V ) is the following:
w=−PΔV
where,
ΔV=V2−V1
It was stated that the gas is expanding, then the work is done by the system and it is of a negative value .
Note that work, should be expressed in 1L⋅atm=101.3J
CHECK THE ATTACHMENT FOR DETAILED EXPLATION
<u>Answer: </u>The concentration of
in the solution is 
<u>Explanation:</u>
pH is defined as the negative logarithm of hydrogen ion concentration present in the solution.
.....(1)
We are given:
pH of solution = 2.5
Putting values in equation 1, we get:
![2.5=-\log [H^+]](https://tex.z-dn.net/?f=2.5%3D-%5Clog%20%5BH%5E%2B%5D)
![[H^+]=10^{-2.5}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-2.5%7D)
![[H^+]=3.16\times 10^{-3}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D3.16%5Ctimes%2010%5E%7B-3%7DM)
Hence, the concentration of
in the solution is 
Noble gases are all elements in column 18. aka far right