تحليل الماء الكهربائي

تحليل الماء إلى غاز الهيدروجين والأكسجين

Electrochemistry Intermediate (High School) 40 دقيقة ~$15,00

الهدف

تحليل الماء إلى غاز الهيدروجين والأكسجين باستخدام التحليل الكهربائي، والتحقق من نسبة الحجم 2:1 المتوقعة من الكيمياء الحسابية.

الخلفية

Water electrolysis uses electrical energy to drive the non-spontaneous decomposition of water. At the cathode, water is reduced to hydrogen gas; at the anode, water is oxidized to oxygen gas. A small amount of electrolyte (sulfuric acid or sodium sulfate) is added to increase conductivity.

تحذيرات السلامة

  • Hydrogen gas is flammable — no open flames nearby
  • Do not use excessive voltage (above 12V)
  • Ensure proper ventilation

معدات الوقاية الشخصية المطلوبة

goggles lab_coat

المواد

  • Distilled water (500 mL)
  • Sodium sulfate (Na₂SO₄) (5 g)
    Electrolyte
  • Universal indicator (5 mL)
    Optional, to show pH changes

المعدات

9V battery or DC power supply Two graphite or platinum electrodes Two inverted graduated cylinders or test tubes Beaker (600 mL) Wires with alligator clips Stand and clamps

الإجراء

1

Dissolve 5 g of sodium sulfate in 500 mL of distilled water in the beaker.

3 دقيقة
2

Fill two graduated cylinders completely with the solution and invert them over the electrodes in the beaker.

5 دقيقة
3

Connect the electrodes to the DC power supply or battery. Note which electrode is connected to positive (anode) and negative (cathode).

3 دقيقة
4

Turn on the power supply and observe gas bubbles forming at both electrodes.

2 دقيقة
5

Collect gas in the inverted cylinders for 15-20 minutes, recording the volume at each electrode every 5 minutes.

20 دقيقة Keep flames away — hydrogen is flammable
6

Compare the volumes of gas collected. The cathode (H₂) should collect twice the volume of the anode (O₂).

3 دقيقة
7

Optionally, test the cathode gas with a lit splint (squeaky pop test for H₂) and the anode gas with a glowing splint (relights for O₂).

3 دقيقة Use small quantities for gas tests

النتائج المتوقعة

The cathode should collect approximately twice the volume of gas as the anode, confirming the 2:1 ratio of H₂ to O₂. If universal indicator is added, the solution near the cathode turns blue/purple (basic) and near the anode turns red/orange (acidic).

التنظيف

Disconnect the power supply. Dispose of the solution down the drain. Rinse and dry the electrodes.

التفاصيل

الفئة
Electrochemistry
الصعوبة
Intermediate (High School)
المدة
40 دقيقة
التكلفة التقديرية
$15,00
الخطوات
7
المواد
3

مزيد من التجارب

التحقق من سلسلة النشاط 30 min الطلاء الكهربائي بالنحاس 60 min بطارية الليمون 20 min بناء خلية دانيال 45 min تحليل كبريتات النحاس كهربائياً 50 min خلية التركيز 45 min طرق منع الصدأ 30 min قياس إمكانية الخلية الفولتية 60 min

Frequently Asked Questions

What is the objective of تحليل الماء الكهربائي?
تحليل الماء إلى غاز الهيدروجين والأكسجين باستخدام التحليل الكهربائي، والتحقق من نسبة الحجم 2:1 المتوقعة من الكيمياء الحسابية.
How difficult is تحليل الماء الكهربائي?
This experiment is rated as Intermediate (High School). It takes approximately 40 minutes to complete.
What safety precautions are needed for تحليل الماء الكهربائي?
Key safety precautions include: Hydrogen gas is flammable — no open flames nearby; Do not use excessive voltage (above 12V); Ensure proper ventilation.
What materials are needed for تحليل الماء الكهربائي?
The main materials required are: Distilled water, Sodium sulfate (Na₂SO₄), Universal indicator.
What results should I expect from تحليل الماء الكهربائي?
The cathode should collect approximately twice the volume of gas as the anode, confirming the 2:1 ratio of H₂ to O₂. If universal indicator is added, the solution near the cathode turns blue/purple (basic) and near the anode turns red/orange (acidic).