Answer:
a) 3.98 x 10^-10
Explanation:
Hello,
In this case, for the given pH, we can compute the concentration of hydronium by using the following formula:
![pH=-log([H^+])](https://tex.z-dn.net/?f=pH%3D-log%28%5BH%5E%2B%5D%29)
Hence, solving for the concentration of hydronium:
![[H^+]=10^{-pH}=10^{-9.40}\\](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E%7B-pH%7D%3D10%5E%7B-9.40%7D%5C%5C)
![[H^+]=3.98x10^{-10}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D3.98x10%5E%7B-10%7DM)
Therefore, answer is a) 3.98 x 10^-10
Best regards.
Answer:
(-1) is the slope of a graph of In(y+3) on the vertical axis versus In(x-2) on the horizontal axis.
Explanation:

Taking natural logarithm on both the sides:
![\ln [(y+3)]-\ln[2]=\ln [b]-\ln [(x-2)]](https://tex.z-dn.net/?f=%5Cln%20%5B%28y%2B3%29%5D-%5Cln%5B2%5D%3D%5Cln%20%5Bb%5D-%5Cln%20%5B%28x-2%29%5D)
![\ln [(y+3)]=\ln[2]+\ln [b]-\ln [(x-2)]](https://tex.z-dn.net/?f=%5Cln%20%5B%28y%2B3%29%5D%3D%5Cln%5B2%5D%2B%5Cln%20%5Bb%5D-%5Cln%20%5B%28x-2%29%5D)
![\ln [(y+3)]=\ln {[2\times b]-\ln [(x-2)]](https://tex.z-dn.net/?f=%5Cln%20%5B%28y%2B3%29%5D%3D%5Cln%20%7B%5B2%5Ctimes%20b%5D-%5Cln%20%5B%28x-2%29%5D)
Slope intercept form is generally given as:

m = slope, c = intercept on y axis or vertical axis
On rearranging equation:
![\ln [(y+3)]=(-1)\times \ln [(x-2)]+\ln {2b}](https://tex.z-dn.net/?f=%5Cln%20%5B%28y%2B3%29%5D%3D%28-1%29%5Ctimes%20%5Cln%20%5B%28x-2%29%5D%2B%5Cln%20%7B2b%7D)
y = ln [(y+3)], x = ln [(x-2)], m=-1 , c = ln 2b
(-1) is the slope of a graph of In(y+3) on the vertical axis versus In(x-2) on the horizontal axis.
Reduction <span>always results in a lowering of the oxidation number. The reaction of the system above is written as:
</span><span>Cu2+(aq) + Fe(s) --> Cu(s) + Fe2+(aq)
</span>
From the reaction, we see that copper goes from the +2 to a neutral charge. Lowering of the oxidation number happens so this is the element that is being reduced.
Answer:
CuSO4 + 2 NaOH = Cu(OH)2 + Na2SO4
First, we will get the average pH of the two given values:
average pH = (6.4+8) / (2) = 7.2
At this average pH, the concentration of the acid from the phenol red is equal to the concentration of the base.
pH = 7.2
[H+] = 10^(-7.2) = 6.3 * 10^-8
Phenol red has the general formula HA, this gives us:
HA <.......> H+ + A-
At pH = 7.2, [H+] = [A-]
<span>Ka = [H+][A-]/ [HA]
</span>Ka = [H+] = <span>6.3 x 10^-8</span>