# Is fire or ember hotter? **URL:** \ **Category:** Factual Questions\ **Created:** [December 11, 2005, 1:00pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128 "2005-12-11T13:00:25Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![magina](https://avatars.discourse-cdn.com/v4/letter/m/a88e4f/32.png) [@magina](https://boards.straightdope.com/u/magina)\ **Post date:** [December 11, 2005, 1:00pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/1 "2005-12-11T13:00:25Z")
Hei there people! Is fire OR ember hotter? Ember:a hot fragment of wood or coal that is left from a fire and is glowing or smoldering wordnet.princeton.edu/perl/webwn ---
**Author:** ![FlyingRamenMonster](https://avatars.discourse-cdn.com/v4/letter/f/ce7236/32.png) [@FlyingRamenMonster](https://boards.straightdope.com/u/FlyingRamenMonster)\ **Post date:** [December 11, 2005, 4:17pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/2 "2005-12-11T16:17:14Z")
Fire. Fire becomes embers when the temperature is no longer high enough to sustain a fire. Fire is the rapid oxidation of something, for instance a piece of wood in oxygen. The wood oxidises to become charcoal and water, releasing a large amount of energy which heats up the surrounding air and makes it glow. That is fire. Fire is hot air, embers are hot whatever-you-were-burning (in this case, wood). Embers are not hot enough to heat the air and make it glow, otherwise that would be fire. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [December 11, 2005, 4:27pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/3 "2005-12-11T16:27:21Z")
FTR, my Fluke thermocouple meter generally reads flame temperature above 1800-2000 F (2000 is the upper limit) in my fireplace. Resting against the embers reads about 800-900 F max. ---
**Author:** ![Finagle](https://avatars.discourse-cdn.com/v4/letter/f/b19c9b/32.png) [@Finagle](https://boards.straightdope.com/u/Finagle)\ **Post date:** [December 11, 2005, 5:02pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/4 "2005-12-11T17:02:01Z")
> [@FlyingRamenMonster](#): > > Fire. Fire becomes embers when the temperature is no longer high enough to sustain a fire. Fire is the rapid oxidation of something, for instance a piece of wood in oxygen. The wood oxidises to become charcoal and water, releasing a large amount of energy which heats up the surrounding air and makes it glow. That is fire. Fire is hot air, embers are hot whatever-you-were-burning (in this case, wood). Embers are not hot enough to heat the air and make it glow, otherwise that would be fire. I’m not convinced that your reasoning here is correct. My understanding was that fire was the volatile components of the fuel oxidizing. If fire was simply hot air, then you’d see flames shooting out of steel foundries instead of just pools of glowing liquid. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [December 11, 2005, 5:27pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/5 "2005-12-11T17:27:51Z")
It’s not correct. The bright part of fire is the combustion front of the devolatized or otherwise burning items (since they need not be devolatized provided the temperature and partial pressure of air are both high enough) which glows due to the energy released, along with products and partial products of combustion glowing as they are heated and release visible energy. Depending on the products and partial products (related to the combustion efficiency and many other things), different colours of flame can be produced. In my Staff Report I did on where the hottest part of a flame is I talked a bit on this as well. ---
**Author:** ![FlyingRamenMonster](https://avatars.discourse-cdn.com/v4/letter/f/ce7236/32.png) [@FlyingRamenMonster](https://boards.straightdope.com/u/FlyingRamenMonster)\ **Post date:** [December 11, 2005, 5:31pm UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/6 "2005-12-11T17:31:23Z")
:smack: I know I shouldn’t have deleted my three paragraphs. Maybe I should just stay out of GQ from now on. ---
**Author:** ![magina](https://avatars.discourse-cdn.com/v4/letter/m/a88e4f/32.png) [@magina](https://boards.straightdope.com/u/magina)\ **Post date:** [December 12, 2005, 3:55am UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/7 "2005-12-12T03:55:25Z")
> [@Una Persson](#): > > FTR, my Fluke thermocouple meter generally reads flame temperature above 1800-2000 F (2000 is the upper limit) in my fireplace. Resting against the embers reads about 800-900 F max. Hei Serious? Wow, that’s the best evidence that fire is hotter than ember! ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [December 12, 2005, 4:10am UTC](https://boards.straightdope.com/t/is-fire-or-ember-hotter/335128/8 "2005-12-12T04:10:48Z")
> [@magina](#): > > Hei Serious? > > Wow, that’s the best evidence that fire is hotter than ember! Sure, my little Fluke meter is good for more than testing ovens so I can cook my butterscotch bread. Note that actual temperatures will vary greatly depending upon the fuel and firing conditions and where in the fire you stick the thermocouple probe.