증기압과 끓는점

온도에 따른 증기압 변화 측정하기

Gas Laws Advanced (University) 45 분 ~$12.00

목표

다양한 온도에서 물의 증기압을 측정하고 클라우지우스-클라페이론 방정식을 검증한다.

배경

The vapor pressure of a liquid increases exponentially with temperature. By measuring the temperature at which water boils under different reduced pressures (or measuring vapor pressure at different temperatures), the enthalpy of vaporization can be determined from the Clausius-Clapeyron equation.

안전 경고

  • Handle vacuum apparatus carefully — implosion risk with glass
  • Hot water can cause burns
  • Use proper vacuum-rated glassware only

필수 개인 보호 장비

goggles lab_coat

재료

  • Distilled water (200 mL)
  • Ice (500 g)
    For cold water bath

장비

Round-bottom flask (500 mL) Vacuum pump or syringe Pressure gauge or manometer Thermometer Hot plate Rubber tubing Graph paper

실험 절차

1

Set up the flask with water, thermometer, and pressure gauge. Connect to the vacuum pump.

5 분 Use vacuum-rated glassware only
2

Heat the water to 80°C. Record the temperature and vapor pressure.

5 분
3

Reduce pressure with the vacuum pump. Note the temperature at which boiling begins.

5 분
4

Record at least 8 temperature-pressure data points from 40°C to 100°C.

15 분
5

Plot ln(P) vs 1/T(K). The slope = -ΔHvap/R.

10 분
6

Calculate ΔHvap from the slope. Compare with the literature value of 40.7 kJ/mol.

5 분

예상 결과

The ln(P) vs 1/T plot should be linear with a negative slope. The calculated ΔHvap should be approximately 40-44 kJ/mol, close to the accepted value of 40.7 kJ/mol for water.

정리

Release vacuum slowly. Turn off heater. Drain water and dry apparatus.

세부 정보

카테고리
Gas Laws
난이도
Advanced (University)
소요 시간
45 분
예상 비용
$12.00
단계
6
재료
2

더 많은 실험

마그네슘을 이용한 기체 화학양론 40 min 데카르트 잠수함 15 min 풍선으로 보는 샤를의 법칙 30 min 보일의 법칙 검증 40 min 표준 상태에서 기체의 몰부피 35 min 수소 기체 포집 35 min 확산 속도 비교(그레이엄의 법칙) 30 min CO₂와 석회수 시험 20 min

Frequently Asked Questions

What is the objective of 증기압과 끓는점?
다양한 온도에서 물의 증기압을 측정하고 클라우지우스-클라페이론 방정식을 검증한다.
How difficult is 증기압과 끓는점?
This experiment is rated as Advanced (University). It takes approximately 45 minutes to complete.
What safety precautions are needed for 증기압과 끓는점?
Key safety precautions include: Handle vacuum apparatus carefully — implosion risk with glass; Hot water can cause burns; Use proper vacuum-rated glassware only.
What materials are needed for 증기압과 끓는점?
The main materials required are: Distilled water, Ice.
What results should I expect from 증기압과 끓는점?
The ln(P) vs 1/T plot should be linear with a negative slope. The calculated ΔHvap should be approximately 40-44 kJ/mol, close to the accepted value of 40.7 kJ/mol for water.