[cvn]

hi, ive a question here..

i was heating a piece of Mg ribbon on the burner. after sometime it turns red and starts to glow. but when i put if out of flame, the glowing stops, until i put it back on flame.

why is that so? it shld continue glow and burning even if i put it out of flame  

[mrdeadman]

No... what you are doing is heating it up... and when metal gets hot, it turns red, when you take it out of the flame, it cools off and goes back to the original color.

[cvn]

it already glow, and i've put the Mg ribbon on the flame for a long time, say a minute? it's still glowing, but after i take it out, its gone.

after the whole experiment, whats left is i believe, MgO. 

[mike]

Are you sure it is magnesium ribbon. When I put magnesium ribbon in a bunsen flame it ignites into a very bright white flame for a short time until it is all reacted to form MgO.

[cvn]

yeah i'm sure it's magnesium ribbon... 

[Borek]

yeah i'm sure it's magnesium ribbon... 

Mike question is not an unfounded one. If it is magnesium ribbon it should behave like one; it doesn't.

[P]

Leave it under the flame for longer  -  preferably on the tip of the cone of a blue flame (it's hotter there) - Don't take it out when it glows, just let it get hotter --  it will suddenly give off an amazing bright, piercing white light which will make you go "WOOOW  thats nice"

My chem teacher back at school burnt some in a gas jar of pure oxygen.   I loved burning Mg so much I asked here if I could Have a go   -  flouting all health and safety regs she said "well aright then, but be carefull"   --  excellent!  Bit scary at the time but beautiful.

[constant thinker]

Don't stare at burning magnesium. Your eyes will hate you for life after.

I would have to agree with what Borek said. If it's Mg it'll act like it. Maybe try what P said.

Also in your bunsen burner, are you getting a nice blue flame or a yellow-orange flame. If your getting a yellow-orange flame, open up the air valve more until you get a nice blue flame. The blue flame is hotter. Also stick the tip of the ribbon into the flame.