Answer:
6.92; neutral
Explanation:
Kw = [H^+][OH^-] = 1.47 × 10^-14
pKw = pH + pOH = 13.83
At neutrality, [H^+] = [OH^-] and pH = pOH
2pH = 13.83
pH = 6.92
The pH will be 6.92.
At 303 K, this will be the neutral pH, because [H^+] = [OH^-]
Answer:
Ka = 3.50x10⁻⁴
Explanation:
First, we need to convert the unit of 3.60 g/L to mol/L:
The reaction dissociation of aspirin in water is:
C₉H₈O₄ + H₂O ⇄ C₉H₇O₄⁻ + H₃O⁺
0.02 - x x x
The constant of the above reaction is:
![Ka = \frac{[C_{9}H_{7}O_{4}^{-}][H_{3}O^{+}]}{[C_{9}H_{8}O_{4}]}](https://tex.z-dn.net/?f=%20Ka%20%3D%20%5Cfrac%7B%5BC_%7B9%7DH_%7B7%7DO_%7B4%7D%5E%7B-%7D%5D%5BH_%7B3%7DO%5E%7B%2B%7D%5D%7D%7B%5BC_%7B9%7DH_%7B8%7DO_%7B4%7D%5D%7D%20)
To find Ka we need to find the value of x. We know that pH = 2.6 so:
![pH = -log[H_{3}O^{+}]](https://tex.z-dn.net/?f=%20pH%20%3D%20-log%5BH_%7B3%7DO%5E%7B%2B%7D%5D%20)
![x = 2.51 \cdot 10^{-3} M = [H_{3}O^{+}] = [C_{9}H_{7}O_{4}^{-}]](https://tex.z-dn.net/?f=%20x%20%3D%202.51%20%5Ccdot%2010%5E%7B-3%7D%20M%20%3D%20%5BH_%7B3%7DO%5E%7B%2B%7D%5D%20%3D%20%5BC_%7B9%7DH_%7B7%7DO_%7B4%7D%5E%7B-%7D%5D%20)
Now, the concentration of C₉H₈O₄ is:
Finally, Ka is:
![Ka = \frac{[C_{9}H_{7}O_{4}^{-}][H_{3}O^{+}]}{[C_{9}H_{8}O_{4}]} = \frac{(2.51 \cdot 10^{-3})^{2}}{0.018} = 3.50 \cdot 10^{-4}](https://tex.z-dn.net/?f=%20Ka%20%3D%20%5Cfrac%7B%5BC_%7B9%7DH_%7B7%7DO_%7B4%7D%5E%7B-%7D%5D%5BH_%7B3%7DO%5E%7B%2B%7D%5D%7D%7B%5BC_%7B9%7DH_%7B8%7DO_%7B4%7D%5D%7D%20%3D%20%5Cfrac%7B%282.51%20%5Ccdot%2010%5E%7B-3%7D%29%5E%7B2%7D%7D%7B0.018%7D%20%3D%203.50%20%5Ccdot%2010%5E%7B-4%7D%20)
Therefore, the Ka of aspirin is 3.50x10⁻⁴.
I hope it helps you!
The number of electrons in an atom's outermost valence shell governs its bonding behaviour. Elements whose atoms have the same number of valence electrons are grouped together in the Periodic Table. ... Nonmetals tend to attract additional valence electrons to form either ionic or covalent bonds.
K= 8
C=4
O= 12
The number after the letter shows how much of that atom there is.
The 4 shows there is 4 of each after it, so 4 of the K2, C, and O3. You would want to multiply the K2, C, and O3 by 4.
