Name: 03 - 氫氣和氧氣的測試 (03 - Tests for hydrogen and oxygen gas)
Uploaded: 2021-01-14T06:44:26.000Z
Duration: 3 min 2 s
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Hello. In this video I'm going to perform two very popular and widely known tests

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

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.

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.

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

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

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