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  • Hello. In this video I'm going to perform two very popular and widely known tests

  • for the presence of hydrogen and oxygen.

  • First, the test for hydrogen. Get 10 mL of dilute hydrochloric acid

  • and add them to a test tube. Next, get a small piece of metal

  • that is more reactive than hydrogen in the electrochemistry series.

  • The most common metals used for this purpose are magnesium, zinc

  • iron and aluminum. I'm using magnesium.

  • OK, here's what happens; magnesium reacts with hydrochloric acid

  • yielding hydrogen gas and magnesium chloride that stays in solution.

  • This is a graphic explanation of the reaction.

  • Now the test for hydrogen. Notice the "popping" sound.

  • Moving on to the test for oxygen.

  • The first thing you need to do is to place a few crystals of potassium permanganate in a container.

  • Add 100 mL of water and swirl to completely dissolve it.

  • Very carefully pour 50 mL of diluted hydrogen peroxide.

  • I diluted mine by mixing 25 mL of 30% hydrogen peroxide

  • with 25 mL of water. So the concentration now is 15%.

  • Potassium permanganate reacts with hydrogen peroxide

  • yielding potassium superoxide, oxygen gas, manganese dioxide and water.

  • The reaction is almost complete now. I'm adding what's left in my beaker.

  • Now for the test. I light the match

  • and bring it close to the flask. And, as you can see,

  • the flame is much brighter.

  • So these were the easy ways to test for hydrogen and oxygen.

  • Thanks for watching! Please subscribe, like and leave a comment.

Hello. In this video I'm going to perform two very popular and widely known tests

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B2 中高級

03 - 氫氣和氧氣的測試 (03 - Tests for hydrogen and oxygen gas)

  • 23 1
    Yrchinese 發佈於 2021 年 01 月 14 日
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