Calculate how many grams of NaOH must be added to 75.0 ml of H2SO4 1,000m to get a tampon that has pH = 1,920
To calculate how many grams of NaOH must be added to 75.0 ml of 1,000m H2SO4 solution to obtain a pH of 1,920, we need to understand the concept of pH and how it relates to the concentration of hydrogen ions (H⁺) in a solution.
First, let's calculate the initial concentration of H⁺ in the H2SO4 solution. Since the solution has a pH of 1,000m, we can use the pH formula:
pH = -log[H⁺]
Rearranging the formula, we get:
[H⁺] = 10 ^ (-pH)
Substituting the given pH value:
[H⁺] = 10 ^ (-1,000)
Next, to achieve the desired pH of 1,920, we need to calculate the concentration of H⁺ in the final solution. Again, using the pH formula:
[H⁺] = 10 ^ (-pH)
Substituting the desired pH value:
[H⁺] = 10 ^ (-1,920)
Now, let's find the concentration of OH⁻ in the final solution, as NaOH is a strong base that reacts with H⁺ to form water:
[OH⁻] = 14 (since water is neutral)
Since water is neutral and the sum of pH + pOH in a neutral solution is equal to 14, we can calculate the pOH using the formula:
pOH = 14 - pH
Given that the desired pH is 1,920, we can find the pOH as follows:
pOH = 14 - 1,920
Finally, we have the concentration of OH⁻ ions:
[OH⁻] = 10 ^ (-pOH)
Now, using the balanced chemical equation for the reaction between NaOH and H2SO4:
2 NaOH + H2SO4 -> Na2SO4 + 2 H2O
We can see that it takes 2 moles of NaOH to neutralize 1 mole of H2SO4. Therefore, we need to find the number of moles of H2SO4 in the initial solution and then use that information to calculate the moles of NaOH required.
To find the moles of H2SO4, we need to know its concentration. However, the given information only provides the volume (75.0 ml). If the concentration of H2SO4 is also given, we can proceed with the calculations. Otherwise, we cannot determine the amount of NaOH required without additional information.
Please provide the concentration of H2SO4 so that we can continue with the calculations.