TBR Chem Thermo Passage 7 Question 49

[Futbol99]

Hey guys,
I think I'm having a slow moment, its 1:00 am, this question is not clicking no matter how much Im trying to force it, and getting frustrated. It's the wording that's confusing me, so if I can get a clear up, I'd appreciate it!

Question:
In calculations, it can be assumed that the heat capacity of 0.1 M HCl is equal to that of water. If the heat capacity of 0.1 M HCl is greater than the heat capacity of water, how is the calculated value affected?

A. The calculated AH is too small.
B. The calculated AH is too large.
C. The difference is insignificantcomparedto heat lost to the environment.
D. The reaction rate increases, so the thermometer does not accurately record the temperature.

Answer is A. I picked B. I'm reading through the answer explanation, and the way they worded it there makes a lot of sense to why I got this wrong...However, re-reading the question makes me really confused, and I'd probably pick it wrong again, if I encounter it again.

Im not understanding what the question wants...I'm reading it as if it's saying- the heat capacity (which is C) of HCl is greater than Water's heat capacity (C). So if we assumed that HCl heat capacity is equal to the Water's heat capacity, then shouldn't the value we calculate for ∆H be greater than it should be if used a larger C value? Is "Heat capacity" different than "Specific heat capacity" ? If so, how can I understand it through this wording?

Thanks..!! I feel like Im over looking this somewhere

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[WierdScience]

The difference between just capacity and specific heat capacity is that specific factors in mass. So H=mcT for specific and H=CT for just capacity. But this is just simply that you are using the smaller value of water for capacity so the value calculated will be smaller than if you use the correct, larger value for HCL.

 

[Lunasly]

Just wanted more clarification on this. If I am reading the answer explanation correctly, it is saying that if HCl(aq) did have a larger heat capacity than water, then the calculated value for deltaH would be too small given that we have plugged in a smaller value for the heat capacity (i.e., we plugged in the heat capacity of water).

Usually when an answer is provided to these types of questions, it explains what would happen had we used a larger value for the heat capacity (i.e., had we plugged in the heat capacity of HCl, which is larger than water). In this case, the magnitude of deltaH would be larger.

Is the answer explanation just describing the error we would have in our calculation if we had plugged in a value smaller than we were supposed to? If this is the case, then I think this is a poorly worded question.