Phase change
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Re: Phase change
This phase change causes the change in enthalpy to be positive (delta H is positive).
Re: Phase change
Enthalpy will be positive because the molecules must absorb energy to loosen forces on each other and assume more free form.
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Re: Phase change
A positive delta H means energy is put in (endothermic) which is what is necessary to break the bonds that holds a solid together into a liquid. That's why change in enthalpy is positive.
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Re: Phase change
Because the phase change requires energy, there is a + delta H value. Hope this helps
Re: Phase change
Delta H would be positive because the molecules are absorbing energy to "loosen" the bonds.
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Re: Phase change
Delta H is positive since melting is breaking bonds and energy is required in order to do so.
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Re: Phase change
Breaking the bonds that are holding the solid together requires energy. Thus, delta H is positive since the reaction is endothermic (needs energy/energy absorbed).
Re: Phase change
Delta H is positive because energy must be used to break the bonds to turn ice into a liquid
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Re: Phase change
You're going from a state of lower energy to a state of higher energy when you go from a solid to a liquid (or a liquid to a gas) so the change in enthalpy should be positive
Re: Phase change
Because heat (energy) needs to be added to the ice in order to make it undergo a phase change into liquid form, is positive
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Re: Phase change
Delta H is positive when ice turns to liquid (applying heat to change from solid to liquid).
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Re: Phase change
Delta H is positive as the system absorbs energy in order to go to a liquid phase AND the energy remains there to keep it in a liquid phase.
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Re: Phase change
A positive delta H means energy is put in, which makes it endothermic, which is what is necessary to break the bonds that holds a solid together into a liquid. That's why the change in enthalpy is positive!
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