<span>When pKas of polyprotic intermediates have a difference of 2 or more you just average them using the equation: pH = (pKa2 + pKa3) / 2 </span>
<span>pKa2 = -log(Ka2) ; pKa3 = -log(Ka3) </span>
<span>so, for this problem, REGARDLESS OF THE CONCENTRATION GIVEN, the answer is: </span>
<span>pH = (7.2076+12.3767) / 2 </span>
<span>pH = 9.79</span>
Cobalt is a metal thus the atoms are bonded together in giant atomic structures and metallic bonds. The atoms attract each other with very strong atomic forces this the resulting structure is giant atomic structures. This provides for the extra strong structure of cobalt.
The solution would be like
this for this specific problem:
<span><span>
E</span>=</span><span>mc</span>ΔT<span> <span>
= (</span>15<span> g</span><span>)(</span>1.91<span> <span>J<span><span>g∘</span>C</span></span>)(</span>25<span><span> ∘</span>C</span>−15<span><span> ∘</span>C</span><span>)
</span></span>= 28.65 * 10
= 286.5
<span>
I hope this helps and if you have any further questions, please don’t hesitate
to ask again. </span>
Answer: beta, gamma, alpha
Explanation: Beta is weakest gamma is middle alpha is strongest