Answer:
P₄O₆
Explanation:
The molecular formula is a whole number multiple of the empirical formula. that is, if the mole wt is 219.9 gms/mole and the empirical formula weight is 110 gms/mole*, then the whole number multiple is 219.9/110 = 2 => Molecular formula => (P₂O₄)₂ => P₄O₆.
It is d. compounds because they have more than one element.
Explanation:
It <em><u>provides an objective, standardized approach to conducting experiments</u></em> and, in doing so, improves their results. By using a standardized approach in their investigations, scientists can feel confident that they will stick to the facts and limit the influence of personal, preconceived notions.
I hope this helps you out!
The Difference Between Science, Engineering, and Technology. Science is the study of the natural world as it is; engineering is creating new tools, devices, and processes based on scientific knowledge; technology is the sum total of all the engineered tools, devices and processes available.
Answer:
D H2PO4– + HPO42–
Explanation:
The acid dissociation constant for
are
respectively.
![\mathbf{pka (H_3PO_4) = -log (7\times 10^{-3} )=2.2}](https://tex.z-dn.net/?f=%5Cmathbf%7Bpka%20%28H_3PO_4%29%20%3D%20-log%20%287%5Ctimes%2010%5E%7B-3%7D%20%29%3D2.2%7D)
![\mathbf{pka (H_2PO_4^-) = -log (8\times 10^{-8} )=7.1}](https://tex.z-dn.net/?f=%5Cmathbf%7Bpka%20%28H_2PO_4%5E-%29%20%3D%20-log%20%288%5Ctimes%2010%5E%7B-8%7D%20%29%3D7.1%7D)
![\mathbf{pka (HPO_4^{2-}) = -log (5\times 10^{-13} )=12.3}](https://tex.z-dn.net/?f=%5Cmathbf%7Bpka%20%28HPO_4%5E%7B2-%7D%29%20%3D%20-log%20%285%5Ctimes%2010%5E%7B-13%7D%20%29%3D12.3%7D)
The reason while option D is the best answer is that, the value of pKa for both
lies on either side of the desired pH of the buffer. This implies that one is slightly over and the other is slightly under.
Using Henderson-Hasselbach equation:
![\mathbf{pH = pKa + log \Big( \dfrac{HPO_4^{2-}}{H_2PO_4^-} \Big)}](https://tex.z-dn.net/?f=%5Cmathbf%7BpH%20%3D%20pKa%20%2B%20log%20%5CBig%28%20%5Cdfrac%7BHPO_4%5E%7B2-%7D%7D%7BH_2PO_4%5E-%7D%20%5CBig%29%7D)