Answer:
To maintain a pH value of 8.8 in a particular solution the best option is Tris or boric acid.
Explanation:
To decide a good acid/conjugate base pair it is necessary to know the pKa of the acids because every buffer has an optimal effective range due to pH = pKa ± 1. The closer the working pH is to the acid pKa, the buffer will be more effective. Below is the list of the pKa of the different option.
Acetic acid: pKa = 4.76
Boric acid: pKa1 = 9.24 pKa2 = 12.74 pKa3 = 13.80
Ascorbic acid: pKa1 = 4.17 pKa2 = 11.57
Tris: pKa = 8.06
Acetic and Ascorbic acid are too far from the range of 8.8. Thus the best options are boric acid or Tris. To define between these two it is necessary to consider other factors like interaction between components of the solution and the ionic strength required.
Answer : The concentration of 
ion is 0.0375 M.
Explanation :
The balanced equilibrium reaction will be:
The expression for solubility constant for this reaction will be,
![K_{sp}=[Pb^{2+}][Cl^-]^2](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5BPb%5E%7B2%2B%7D%5D%5BCl%5E-%5D%5E2)
Now put all the given values in this expression, we get:
![2.40\times 10^{-4}=[Pb^{2+}]\times (0.0800)^2](https://tex.z-dn.net/?f=2.40%5Ctimes%2010%5E%7B-4%7D%3D%5BPb%5E%7B2%2B%7D%5D%5Ctimes%20%280.0800%29%5E2)
![[Pb^{2+}]=0.0375M](https://tex.z-dn.net/?f=%5BPb%5E%7B2%2B%7D%5D%3D0.0375M)
Therefore, the concentration of ion is 0.0375 M.
Answer:
7
Explanation:
N-14 has 7
i looked it up ye ur probably gonna get it right
Answer:
Thank you for da free points
Explanation:
Answer:
Noble gases are the least reactive of all elements
Explanation:
because they have eight valence electrons, which fill their outer energy level
