oxygen test

[joeb]

hi what is the test for oxygen?its for my sons homework.

[fo3nix]

To test if oxygen is inside a test tube for example (more than air, anyway), put a burning splint inside. It'll glow brighter as it reacts.

[Gef]

I'm sure your son would only be asked that question if he had already seen the test. If not, his Science teacher is a numptie for asking it.

Anyway fo3nix's answer is wrong.

Why can't he do his own homework?

[stevie21]

Oxygen is the only gas which will relight a glowing splint.

[Siamsal]

For pure oxygen, stevie21 has got the test I remember. A smouldering splint, not a burning one.

A test for higher-than-normal oxygen though - no idea.

[fo3nix]

Oops, I am wrong! Showing that I haven't used a bunson burner for 5 years. Stevie's answer was what I was trying to remember.

[ugly_bob]

a flame would go out if there was no (or little) oxygen, so if a flame stays alight, there is oxygen present.

[shammydodger]

Hi Joeb

Just to tidy up the info you've been given and to clarify.

The answer your son's teacher will be looking for is Stevie21's. i.e. the test for oxygen is that it will relight a glowing splint.

It's one of the standard tests that GCSE pupils need to know (I'm assuming your son is of that age and, of course, that he is British). Although the question does not specify PURE oxygen (or oxygen rich atmosphere), it will be what is intended. For atmospheres that contain oxygen amongst significant amounts of other gases, more involved chemical tests are required, which your son will not be required to know at his level.

[Gef]

Excellent answer from shammy. However, and this is no longer part of school chemistry, nitrous oxide will also relight a glowing splint.

[Rabelais]

No longer a part of school chemistry? As a science teacher in the UK I can tell you it is and relighting a glowing splint is indeed the test for Oxygen
http://www.wpbschoolhouse.btinternet.co.uk/pag e13/ChemicalTests/ChemicalTests.htm#oxygen

[theprof]

Rabelais:

I think you've misunderstood the point Gef was making. Gef did not state that the glowing splint test is no longer used in schools as a test for oxygen. He was merely pointing out that nitrous oxide will also reignite a glowing splint.

I knew what he meant as soon as I read the post. To satisfy my own curiosity, I asked a class of undergraduates at my uni on Friday if they knew of any other gas apart from oxygen that would reignite a glowing splint. Not one student put their hand up.

Clearly, as Gef stated, this nitrous oxide test is no longer part of the school curriculum.

Do you know otherwise? If so, let me know the board concerned as I can't find it in the online specs.

[ukbod]

I always thought it was check skin for blueness - if not then oxygen is present

[mandzz84]

Ummm what do you have in the test tube along with the oxygen? it is too for my daughters homework

[mandzz84]

Hiya just want to know what else do you add to the test tube with the oxygen?