Determine the grams of NaOH that could be absorbed by the SO3/HSO3 buffer before the base absorbing capacity of this buffer were destroyed.
You must supply more of the problem than an overview. How much buffer? What is the pH? But you can work the problem is you know how to use the Henderson-Hasselbalch equation. The buffer capacity is met at pH +/- 1 from the initial pH of the buffer.
To determine the grams of NaOH that could be absorbed by the SO3/HSO3 buffer, we first need to understand the concept of base absorbing capacity.
The base absorbing capacity of a buffer refers to the amount of base (in this case, NaOH) that can be added to the buffer system before the buffering capacity is overwhelmed and the pH of the buffer solution changes significantly.
The SO3/HSO3 buffer is made up of sodium sulfite (Na2SO3) and sodium bisulfite (NaHSO3). The equilibrium reaction between these two species can be represented as:
SO3-2 + H2O ↔ HSO3- + OH-
Given that we are assuming the buffering capacity is lost when the pH changes significantly, we should aim for a pH change of +/- 1 unit from the initial pH of the buffer solution.
Step 1: Calculate the concentration of buffer components
Determine the initial concentrations of SO3-2 and HSO3- in the buffer solution. Let's assume that the initial pH is 7, and the concentration of SO3-2 and HSO3- in the buffer is 0.1 M.
Step 2: Calculate the concentration of OH- required to cause a pH change
To cause a pH change of +/-1 unit, a concentration of OH- equal to the initial concentrations of SO3-2 and HSO3- is required. In this case, the concentration of OH- required is also 0.1 M.
Step 3: Calculate the amount of NaOH required to produce the required concentration of OH-
The molar mass of NaOH is 40.0 g/mol. From the equation SO3-2 + H2O ↔ HSO3- + OH-, we know that 1 mole of NaOH will produce 1 mole of OH-. Therefore, 0.1 moles of NaOH is required.
Step 4: Convert moles of NaOH to grams
To determine the grams of NaOH, we need to multiply the moles of NaOH by the molar mass of NaOH.
0.1 moles NaOH x 40.0 g/mol = 4.0 grams NaOH.
Therefore, the grams of NaOH that could be absorbed by the SO3/HSO3 buffer before the base absorbing capacity of this buffer is destroyed is 4.0 grams.
To determine the grams of NaOH that could be absorbed by the SO3/HSO3 buffer before its base absorbing capacity is destroyed, you need to consider the buffer's capacity and the stoichiometry of the reaction.
1. Find the moles of the buffer components: SO3 and HSO3. Look up the molar masses of sodium sulfite (SO3) and sodium bisulfite (HSO3) in a periodic table or reference source. Let's assume the molar masses are 82 g/mol and 104 g/mol, respectively.
2. Calculate the moles of SO3 and HSO3 in the buffer solution. Let's assume you have 100 mL of the buffer solution with a known concentration of SO3 and HSO3. Calculate the moles of each component using the concentration and volume, and convert to moles.
3. Determine the stoichiometry of the reaction. Balance the equation for the reaction of NaOH with SO3 and HSO3. It might look something like this:
2 NaOH + SO3 → Na2SO4 + H2O
2 NaOH + HSO3 → NaHSO4 + H2O
4. Identify the limiting reagent. Compare the moles of NaOH in the buffer solution to the stoichiometry of the reaction. Whichever component has the lowest moles relative to the stoichiometry will be the limiting reagent.
5. Use the stoichiometry to calculate the moles of NaOH that react with the limiting reagent. This will give you the maximum amount of NaOH that can be absorbed by the buffer.
6. Convert the moles of NaOH to grams. Multiply the moles of NaOH by its molar mass to obtain the mass in grams.
Keep in mind that this calculation assumes 100% efficiency and ideal conditions. In reality, other factors like pH changes and side reactions can affect the overall acid-base capacity of the buffer.