Uncertainty in the concentration of sodium

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Concentration of NaOH:

• Molar mass of KHP (potassium hydrogen phthalate) = 204.22 g/mol
• Volume of NaOH solution used (in liters) = 25.06 mL * (1 L / 1000 mL) = 0.02506 L
• Mass of KHP = 0.4016 g
• Moles of KHP (assuming KHP reacts 1:1 with NaOH) = mass of KHP / molar mass of KHP = 0.4016 g / 204.22 g/mol = 0.00196 mol
• Concentration of NaOH (in mol/L) = moles of KHP / volume of NaOH solution = 0.00196 mol / 0.02506 L = 0.0785 mol/L

Uncertainty in Concentration:

• Uncertainty in volume (assuming 0.05 mL represents standard deviation) = 0.05 mL * (1 L / 1000 mL) = 5.00 * 10^-5 L
• Using propagation of error, the uncertainty in concentration can be estimated as:
  • uncertainty_concentration = concentration_naoh * (uncertainty_volume / volume_naoh)
  • uncertainty_concentration = 0.0785 mol/L * (5.00 * 10^-5 L / 0.02506 L) = 0.0002 mol/L

Results:

• Concentration of NaOH: 0.0785 mol/L
• Uncertainty in concentration: ±0.0002 mol/L

The concentration of the sodium hydroxide solution is 0.0785 mol/L with an uncertainty of ±0.0002 mol/L. This uncertainty is likely due to the uncertainty in the measured volume of the NaOH solution.

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