On Mon, Oct 27, 2014 at 3:37 PM, Jed Rothwell <jedrothw...@gmail.com> wrote:

> H Veeder <hveeder...@gmail.com> wrote:
>
>
>> ​Unless heat is absorbed during charging and is released during discharge
>> a calorimeter can't tell you if an endothermic reaction occurred.
>>
>
> "The heat being absorbed" is the definition of an endothermic reaction.
> That's exactly what it is. Even if the energy is not subsequently released,
> you can still see the deficit during the storage phase. That is to say, if
> you were to charge up a battery but not later discharge it, then you would
> see a deficit with no compensating exothermic reaction following that. When
> you removed the battery from the calorimeter it would be fully charged up.
>
>
​From the point of the calorimeter heat is not absorbed since no heat
vanishes. Like all measuring instruments a calorimeter is incapable of
doing anything other than it was designed to do and that consists in
detecting changes or lack of changes in heat content. Whether or not the
data it supplies  represents exothermic or endothermic reactions requires
further interpretation based on additional knowledge.

​

> The only exception to this would be if the endothermic phase occurs over a
> very long time and the deficit is very small. It might be too small to
> detect with a given calorimeter. It might then be released as a short
> burst. We can rule out this scenario for most cold fusion experiments,
> including McKubre's, because the periods when there is no heat are shorter
> than the continuous periods when there is heat. So the deficit would have
> to be as large or larger than the positive heat release.
>
>
>

Whether or not an excess heat event is long or short is relative to when
the accounting period begins.
Does he include the time and energy spent loading?​




> You also need a-priori knowledge of how the energy is stored.
>>
>
> No, you don't. Energy is energy. All energy in all forms is either stored
> or it converts to heat. Because entropy.
>
>
​The calorimeter doesn't tell you there is a "deficit".  The only thing it
tells you is how much and how quickly the heat content of the system
changes.The "deficit" is an *interpretation* of this raw data.​
​



>
>> The calorimeter by itself only tells you that there was a mildly
>> exothermic reaction followed by more intense exothermic reaction.
>>
>
> No, the two would have to balance in intensity if they were roughly of the
> same duration. As I said in most cases endothermic phase would have to be
> shorter so it would be more intense and easier to measure.
>
>

>
>> Charging a battery is endothermic because it absorbs *electrical* energy,
>> not because it absorbs *heat* energy.
>>
>
> Other reactions that absorb heat energy (or any other form or source of
> energy) show a similar pattern in a calorimeter. For example, reactions
> that absorb laser light energy will also show a deficit -- assuming you
> measure the laser input correctly, which can be tricky.
>
>
To repeat, unless the temperature falls a calorimeter by itself cannot tell
you if an endothermic process has occurred. You need additional information
to interpret the meaning of the lack of rise in temperature .





> A battery happens to be a convenient way to demonstrate this but any
> endothermic reaction will do.
>
>
>
>> If a calorimeter were good at detecting all types of endothermic
>> reactions then you could substitute them for volt meters.
>>
>
> Well, a watt meter, not a volt meter. Yes, you can, and the instrument
> makers do. All high-quality, high-powered wattmeters use calorimetry. That
> is to say the heat up a resistor wired in series with the load, measure the
> temperature and convert that to power. This method eliminates any
> possibility of exotic waveforms or extremely rapid changes in electric
> power being missed by the instrument. This method detects every joule of
> electricity, no matter what.
>
>
​Of course, but you need to know what is causing the temperature change.

harry

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