الكيمياء

Accumulators

To set up a simple accumulator and demonstrate the possibility of storing energy as chemical energy.

الكيمياء الكهربائية
accumulator; rechargeable cell; lead-acid

ما يتعلمه الطلاب

الجانب العلمي وراء هذه التجربة

There is a class of galvanic cells in which the electrolysis can be reversed. These cells can be charged by an electric current and then later produce a current by reversing the electrode reactions. During charging the energy is stored as chemical energy, and the cells are sometimes called accumulators.

المعدات المستخدمة

  • Connecting wires, red — 2522.03-04
  • Connecting wires, black — 2522.04-08
  • Crocodile clips — 2531.52
  • Lead electrodes — 4716.24
  • Test cell covers — 4718.10
  • Beaker 50 ml — 1118.15
  • Lamp holder — 4762.36

المواد الكيميائية والمواد الكاشفة

  • Sulphuric acid 0.5 M — R:35 S:26-30-45

ملاحظات السلامة

  • Lead compounds produced during the process are poisonous and harmful to the environment. Always wear protective goggles and gloves.

أسئلة للطلاب

  • What voltage did you measure on the starting cell?
  • What happens during the charge process?
  • What voltage did you measure after the charge process?

ما يمكن توقعه

<p>A 0 Volt difference of potential is measured since the half cells are the same, both metals and concentration of the solution.</p><p>A current is produced in the circuit and electrolysis produces bubbles at the electrodes because of the electrolysis that occurs producing oxygen and hydrogen.</p><p>During this time electrodes accumulate an electric charge. REACTIONS.</p><p>By passing an electric current through the cell, electrolysis occurs Pb SO4 + 2e – → Pb + SO42– Cathode (+).</p><p>Pb SO4 + 2 H2O → PbO2 + 4H+ + SO42 + 2 e– Anode (–).</p><p>There is also some production of oxygen (cathode) and hydrogen (anode),because of the electrolysis of water.</p><p>Because the lead dioxide has a brown colour and the lead is grey, the electrodes look different and a new cell with different electrodes has been created.</p><p>The difference of potential between the electrodes is approximately 2 V. When the current supply is suspended, electrolysis ceases.</p><p>The charges accumulated on the electrodes are discharged because the reaction can be inverted.</p><p>When the energy in the cell is used, the reactions reverse as follows.</p><p>PbO2 + H2SO4 + 2 e– → Pb SO4 + H2O Cathode (+).</p><p>Pb + SO42– → Pb SO4 + 2 e–Anode (–).</p><p>So during these processes the oxidation state of lead changes.</p><p>The lamp lights up and a current reading is displayed.</p><p>The current slowly decreases until the bulb goes out. The accumulator is now discharged but it is possible to recharge it again.</p>

التخلص

Dispose of the liquids into the waste container.

قم بإجراء هذه التجربة في فصلك الدراسي

تُعد هذه التجربة جزءًا من برنامج «مختبر العلوم المتنقل» (ATP) Mobile Lab — وهو مختبر متكامل يحول الفصل الدراسي العادي إلى مختبر علوم فعال، ويضم أكثر من 200 تجربة في مجالات الفيزياء والكيمياء والبيولوجيا والروبوتات والهندسة. ويقوم « Gali » — وهو المعلم الذكي المدمج في موقع ATP Connect — بتوجيه الطلاب خلال كل خطوة والإجابة على أسئلتهم أثناء إجراء التجارب.

انظر Mobile Labتواصل مع فريقنا