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GCSE CHEMISTRY: Endothermic Reaction Help

I understand that in endothermic reactions energy is taken in from the surroundings, and that the products have more energy than the reactants. As energy is taken in, I would therefore expect there to be an increase in temperature of the mixture. Therefore, why, in endothermic reactions like https://www.youtube.com/watch?v=GfPJsHM6dsQ, does the temperature decrease? I would really appreciative a good explanation as I always get this confused. Thank you in advance.
the temperate of the surrounding decreases right??
Original post by sfaraj
the temperate of the surrounding decreases right??


Yes, because energy is taken in the energy of the surroundings decreases, have you got onto endothermic calculations yet? That has a positive or negative answer relating to the type of reaction
Original post by sfaraj
the temperate of the surrounding decreases right??


Yeah you're right the surroundings' temperature decreases. I understand this as energy is taken in from them. What I don't understand is how the temperature of the mixture decreases if it gains energy?
(edited 7 years ago)
Original post by Lavender3002
Yeah you're right the surroundings' temperature decreases. I understand this as energy is taken in from them. What I don't understand is how the temperature of the mixture decreases if it gains energy?



did the website or video or whatever say that the mixture decreases???
Original post by ProbablyJade
Yes, because energy is taken in the energy of the surroundings decreases, have you got onto endothermic calculations yet? That has a positive or negative answer relating to the type of reaction


what do you mean by calculations? what board are you doing?
Original post by sfaraj
did the website or video or whatever say that the mixture decreases???


https://www.youtube.com/watch?v=GfPJsHM6dsQ, : The temperature probe is in the mixture so the mixture's temperature has decreased.

"The energy is usually transferred as heat energy, causing the reaction mixture and its surroundings to get colder." BBc bitesize says this.
Oh I think I might have worked it out: The energy that is taken in goes into the reactants to make bonds, so the temperature of the mixture decreases as the energy is used up by the reactants, which is why the products have more energy. This would make sense as in exothermic reactions energy is released to break bonds, and this energy heats the mixture and the surroundings.
Reply 9
What endothermic and exothermic describe is the flow of heat transfer.

If something is exothermic, it means that heat is transfering from the inside to the outside.
That's why something will feel hot if you touch it, because all that heat is being applied to your receptors on your hand, or whatever instrument you use.

If something is endothermic, it means the heat is transfering from the outside to the inside.
That's why something will feel cold if you touch it, because it's drawing the heat away from your hand, or instrument.

The actual substance itself is going to be cold (exothermic) or hot (endothermic).
You're right that if a substance is absorbing energy, it should feel hotter, but the temperature measured is the transfer of heat energy from the medium we use to measure, whether it'd be our hand or a temperature.

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