Certainly! Let's tackle each part of the problem one by one.
### Part 2: Calculate the approximate volume of 0.0995 M NaOH needed to neutralize 25.0 mL of 0.0958 M H2SO4.
First, we should write the balanced chemical equation for the reaction between H₂SO₄ and NaOH:
[tex]\[ \text{H}_2\text{SO}_4 + 2\text{NaOH} \rightarrow \text{Na}_2\text{SO}_4 + 2\text{H}_2\text{O} \][/tex]
From the balanced equation, we can see that one mole of H₂SO₄ reacts with two moles of NaOH.
Step-by-step solution:
1. Calculate the moles of H₂SO₄.
- Molarity (M) = moles/volume (L)
- Volume of H₂SO₄ = 25.0 mL = 25.0/1000 L = 0.025 L
- Moles of H₂SO₄ = 0.0958 M × 0.025 L = 0.002395 moles
2. Determine the moles of NaOH needed.
- From the balanced equation, 1 mole of H₂SO₄ requires 2 moles of NaOH.
- Therefore, moles of NaOH needed = 2 × moles of H₂SO₄ = 2 × 0.002395 moles = 0.00479 moles
3. Calculate the volume of NaOH required.
- Molarity of NaOH = 0.0995 M
- Volume of NaOH (in liters) = moles of NaOH / Molarity of NaOH = 0.00479 moles / 0.0995 M ≈ 0.04814 L
- Convert volume to milliliters: 0.04814 L × 1000 mL/L = 48.14 mL
Thus, the volume of 0.0995 M NaOH needed to neutralize 25.0 mL of 0.0958 M H₂SO₄ is approximately 48.14 mL.
### Part 3: Write an equation (including states) for the combination reaction between carbon dioxide gas and water. Why is this reaction significant in this experiment?
The equation for the combination reaction between carbon dioxide gas (CO₂) and water (H₂O) is:
[tex]\[ \text{CO}_2 (g) + \text{H}_2\text{O} (l) \rightarrow \text{H}_2\text{CO}_3 (aq) \][/tex]
Significance of this reaction:
This reaction forms carbonic acid (H₂CO₃), which is important in many chemical processes, including buffering systems in aqueous solutions. In the context of the experiment, understanding this reaction aids in grasping how dissolved CO₂ can influence the pH and neutrality process during titrations and related calculations.
### Part 4: A student failed to rinse a damp buret with a small amount of the acid before filling it with acid. Will more or less titrant (acid) be required to neutralize the sodium carbonate?
If the student failed to rinse a damp buret with a small amount of the acid solution before filling it, water left in the buret would dilute the acid solution. This means that the concentration of the acid in the buret would be less than intended.
Implication:
Since the acid solution is less concentrated, the student will require more of this diluted titrant (acid) to neutralize the same amount of sodium carbonate. This is because the lower concentration provides fewer moles of hydrogen ions (H⁺) per unit volume, hence necessitating a larger volume to achieve neutrality in the reaction.
