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. answer this question I need them now please thanks 1. What are the components

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Question

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answer this question I need them now please thanks

1. What are the components of a buffer system? 2. Is a solution of citric acid and sodium citrate a buffer. Justify your answer 3. How does a buffer neutralize a strong acid? 4. The K, for lactic acid is 1.4x10. What is its pk, ? 5. Using the Henderson-Hasselbach equation, what is the pH of a buffer when the concentrations of its weak acid and conjugate base are equal? 6. You have the molar solubility of a salt. How do you convert that unit to g/100mL? 7. Write the ion product equation for Ba,(PO,) 8. The solubility of strontium carbonate, SrCO, will (increase / decrease / not be affected) by a decrease in pH. Why?

Explanation / Answer

Q1

A buffer is any type of substance that will resist pH change when H+ or OH- is added.

This is typically achieved with equilibrium equations. Both type of buffer will resist both type of additions.

When a weak acid and its conjugate base are added, they will form a buffer

The equations:

The Weak acid equilibrium:

HA(aq) <-> H+(aq) + A-(aq)

Weak acid = HA(aq)

Conjugate base = A-(aq)

Neutralization of H+ ions:

A-(aq) + H+(aq) <-> HA(aq); in this case, HA is formed, H+ is neutralized as well as A-, the conjugate

Neutralization of OH- ions:

HA(aq) + OH-(aq) <-> H2O(l) + A-(aq) ; in this case; A- is formed, OH- is neutralized as well as HA.

Now,

For the weak base equilibrium:

B(aq) + H2O(l) <-> BH+(aq) + OH-(aq)

Weak base = B;

Conjugate acid = BH+

Neutralization of OH- ions:

BH+(aq) + OH-(aq) <-> B(aq) + H2O(l); in this case, OH- is neutralized by BH+, as well as B is created

Neutralization of H+ ions:

B(aq) + H+(aq) <-> BH+(aq)

Q2

citric acid = H3A

sodium citrate buffer --> Na3A, Na2HA, NaH2A

yes i tis a buffer since:

citric aicd + citrate ion are present (conjguate base)

Q3

a buffer will neutralize acid via:

A- + H+ = HA

conjugate base, A- will accept H+ as proton, it forms the weak acid HA

Q4

pH = pKa + log(A-/HA)

if A- =HA

pH= pKa + log(1)

pH = pKA

Q6

solubility --> mol per liter --> change to mass per liter --> Change to mass per 100 mL