Photo AI

The pKₐ of sulfurous acid in the following reaction is 1.82 - HSC - SSCE Chemistry - Question 36 - 2021 - Paper 1

Question icon

Question 36

The-pKₐ-of-sulfurous-acid-in-the-following-reaction-is-1.82-HSC-SSCE Chemistry-Question 36-2021-Paper 1.png

The pKₐ of sulfurous acid in the following reaction is 1.82. H₂SO₃(aq) + H₂O(l) ⇌ H₃O⁺(aq) + HSO₃⁻(aq) The pKₐ of hydrogen sulfite in the following reaction is 7.1... show full transcript

Worked Solution & Example Answer:The pKₐ of sulfurous acid in the following reaction is 1.82 - HSC - SSCE Chemistry - Question 36 - 2021 - Paper 1

Step 1

The pKₐ of sulfurous acid is 1.82

96%

114 rated

Answer

From the pKₐ value, we can calculate the ionization constant (Kₐ) using the formula:

Ka=10−pKaKₐ = 10^{-pKₐ}

Calculating: Ka(1)=10−1.82=0.01513651248extor1.51imes10−2Kₐ(1) = 10^{-1.82} = 0.01513651248 ext{ or } 1.51 imes 10^{-2}

Step 2

The pKₐ of hydrogen sulfite is 7.17

99%

104 rated

Answer

Similarly, we calculate Kₐ for hydrogen sulfite:

Ka=10−pKaKₐ = 10^{-pKₐ}

Calculating: Ka(2)=10−7.17=0.0000000676extor6.76imes10−8Kₐ(2) = 10^{-7.17} = 0.0000000676 ext{ or } 6.76 imes 10^{-8}

Step 3

Calculate Kₑq for the reaction H₂SO₃(aq) + 2H₂O(l) ⇌ 2H₃O⁺(aq) + SO₃²⁻(aq)

96%

101 rated

Answer

Using the relationship for equilibrium constants:

Keq=Ka(1)imesKa(2)Kₑq = Kₐ(1) imes Kₐ(2)

Substituting the values from the previous calculations: Keq=(1.51imes10−2)imes(6.76imes10−8)Kₑq = (1.51 imes 10^{-2}) imes (6.76 imes 10^{-8})

Calculating:

Keq=1.02imes10−9Kₑq = 1.02 imes 10^{-9}

Join the SSCE students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;