Temperature of sample remaining constant?

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Christian_Ong_3A
Posts: 10
Joined: Fri Jul 22, 2016 3:00 am

Temperature of sample remaining constant?

Postby Christian_Ong_3A » Wed Jan 11, 2017 8:57 pm

I don't quite understand how the temperature of a sample can remain constant if heat is still being added to the system? Wouldn't the heat naturally increase the temperature no matter what?

Shailyn_Moore_3C
Posts: 21
Joined: Wed Sep 21, 2016 2:59 pm

Re: Temperature of sample remaining constant?

Postby Shailyn_Moore_3C » Wed Jan 11, 2017 9:33 pm

Are you talking about like when water stays the same temperature during a phase shift even when heat is being added?

Cliff Danza 3F
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Joined: Wed Sep 21, 2016 2:57 pm
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Re: Temperature of sample remaining constant?

Postby Cliff Danza 3F » Wed Jan 11, 2017 9:37 pm

During phase changes the heat energy being supplied all goes toward breaking bonds and not toward raising temperature.

Makenna Vulgas 1G
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Joined: Wed Sep 21, 2016 3:00 pm

Re: Temperature of sample remaining constant?

Postby Makenna Vulgas 1G » Wed Jan 11, 2017 9:54 pm

Hi! I think you're talking about what Shailyn mentioned with phase changes. When a certain amount of heat is added to water, inducing a phase change from liquid to gas, the temperature of the substance does not change. This is because the heat is being used to break the bonds in the liquid to convert it to a gas. All of heat is being allocated for this purpose so the actual temperature isn't affected. I hope this helps!

Angela To 2B
Posts: 20
Joined: Wed Sep 21, 2016 2:55 pm

Re: Temperature of sample remaining constant?

Postby Angela To 2B » Wed Jan 11, 2017 10:15 pm

If your question is what Shailyn is mentioning, then it's basically what Cliff said! During phase changes, bonds are broken which require energy (and heat is a form of energy)! If you look at a phase change graph, the areas with a horizontal line shows how much energy it can absorb before the sample can no longer retain the state it's in. So the flat area also represents how much energy it takes to break the bond(s), how much heat the sample can absorb before changing phases, as well as temperature!

An example is ice! Ice is usually cold and doesn't really increase in temperature until it's in liquid form. When you have ice in a drink, the drink stays at around the same temperature until all the ice is melted. This is because heat form the surroundings is melting the ice instead of heating up your drink. When all the ice is melted is when the drink starts to increase in temperature, because when ice reaches a certain temperature, it can no longer retain its solid state and undergoes a phase change! I hope this helps!


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