Answer:
Ka = [H₃O⁺] [SO₃²⁻] / [HSO₃⁻]
Kb = [OH⁻] [H₂SO₃] / [HSO₃⁻]
Explanation:
An amphoteric substance as HSO₃⁻ is a substance that act as either an acid or a base. When acid:
HSO₃⁻(aq) + H₂O(l) ⇄ H₃O⁺(aq) + SO₃²⁻(aq)
And Ka, the acid dissociation constant is:
<h3>Ka = [H₃O⁺] [SO₃²⁻] / [HSO₃⁻]</h3><h3 />
When base:
HSO₃⁻(aq) + H₂O(l) ⇄ OH⁻(aq) + H₂SO₃(aq)
And kb, base dissociation constant is:
<h3>Kb = [OH⁻] [H₂SO₃] / [HSO₃⁻]</h3>
Answer:
0.18 L
Explanation:
You can find the volume using the molarity ratio:
Molarity = moles / volume (L)
You can plug the given values into the equation and simplify to find the volume.
Molarity = moles / volume <----- Molarity ratio
2.5 M = 0.45 moles / volume <----- Insert values
(2.5 M) x volume = 0.45 moles <----- Multiply both sides by volume
volume = 0.18 L <----- Divide both sides by 2.5
Question 9. The first one is the smallest. Anything with a negative exponent is going to be less than 1, the .00000241. The exponent tells you the number of zeroes to the right of the decimal point. Farther to right gets smaller and smaller.
Question 10. The last one is true. If the last digit is smaller than 5, drop the digit, and do not change. (If it is a 5 or larger, the digit before it would round up)
According to Hasselbalch equation pH = pKa at the equal point. When pH equals the pKa value of the indicator, the base and acid forms of indicator are present in the ratio of 1:1
(9.3 + 10.5) / 2 =9.9
pKa = 9.9
Using the equation pH = pKa at equal point we get
Ka = 10^- pKa
Ka = 10^- 9.9
Ka = 1.26 x 10^-10
Ka = 1 x 10^-10
