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>
Answer:
I don't know chemistry
Explanation:
because this is the hardest subject in the world nobody can solve it so do yourself ok Beta
The reaction is
FeO + Fe3O4 + 1/2 O2---> 2Fe2O3
Thus as shown in the balanced equation two moles of Fe2O3 are formed when 0.5 moles of O2 reacted with mixture of FeO and Fe3O4
moles of Fe2O3 = MAss / Molar mass = 4.141 / 159.69 = 0.0259 moles
So moles of O2 needed = 0.5 X 0.0259 = 0.01295
Mass of O2 = moles X molar mass = 0.01295 X 32 = 0.4144 grams
Answer:
1+
Explanation:
the number of protons tells you which element it is in the periodic table, you can notice that there is 1 less electron that then there is protons which means that the element had to give 1 electron away. When you get rid of 1 e- you have 1 proton more that electrons so that's why it's 1+
also the element is Cr