Determination of enthalpy change of neutralization

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Determination of enthalpy change of neutralization

• vs

HCI(aq)
NH
(aq)
3
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Dilution of HCl(aq)

• 50.00 cm3 of HCl(aq) was diluted to 250.0 cm3
• Pipette and pipette filler
• Volumetric flask

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Standardization of HCl(aq)

• Burette
• End point of indicator
• Burette reading

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CO32(aq) 2H(aq) ? CO2(g) H2O(l)

• Mole ratio of CO32(aq) to H(aq) is
• 1 2

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Mixing different volumes of HCl(aq) and NH3(aq)

• Measuring cylinder and dropper
• Swirling the mixture
• Taking thermometer readings

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• Initial temperature should be taken
• Recording the highest temperature

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Graph

• Maximum rise in temperature
• Two straight lines are drawn
• The lines pass through (0,0) and (50,0)
• Intersection of the lines is the end point

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(No Transcript)
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Calculation

• Enthalpy change of neutralization
• Negative sign
• kJ mol-1

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Another result

• The molarity of NH3(aq) can be calculated

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Other combinations

• Using standard Na2CO3(aq)
• HCl(aq) vs NH3(aq)
• HCl(aq) vs NaOH(aq)
• Using standard NaOH(aq)
• CH3CO2H(aq) vs NH3(aq)

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Assessment

• Completed within 90 minutes
• Area A and area B both
• Candidates performance
• Standardization of HCl(aq) fair
• Enthalpy change satisfactory
• Graph and result poor