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For questions related to measuring changes in state variables (such as enthalpy) use with the [tag:experimental-chemistry] tag.

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Extrapolating from a calorimetry lab to find a new delta T with different volumes and grams of substance

So, we just finished an AP chem lab where the question was basically: Given the results of the lab were that $\pu{5 grams}$ of $\ce{CaCl2}$ and $\pu{45ml}$ of water produced a $\pu{13.33 ^\circ C}$...
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Temperature differences within static water bath

My question is how much temperature difference could there be between two temperature sensors ~1cm apart in a static water bath, assuming that the sensors are of similar thermal mass? The reason for ...
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Heat transfer problem

For this problem, I'm wondering if the thermos should be involved in the heat transfer because right we have an equation in calorimetry: $q_\text{warm} =-(q_\text{cold} + q_\text{cal})$ A 125 g ...
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Calorific values of biodiesels synthesized from vegetable oils

Calorific values of biodiesels vary depending on the feedstock used in synthesizing it. Although it's not by a lot, is there a particular reason for this? I suspect it's something to do with the ...
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Why are calorimeters often made of materials with low specific heats?

When building calorimeters, a material with a low specific heat is often used (such as Styrofoam, aluminum, etc.). However, why would a material with a low specific heat be preferred? My thought ...
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In what approximations, if any, can we assume a constant temperature in a Bomb calorimeter?

In most, if not all, general chemistry books, you will find that in from constant volume calorimeters, $\Delta H = \Delta U + RT \Delta n_\mathrm{g}$, which is, of course derived from $H = U + PV$. ...
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Is a low specific heat capacity for the material of the calorimeter good or bad?

I wish to ask if a low specific heat capacity of the material of the calorimeter means that the calorimeter would be more exact as it takes less heat for the material to reach equilibrium. I thought ...
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Does specific heat capacity of the container have an effect on the exactitude of a calorimetre?

I'm doing a lab on what is the best material for a calorimetre. I chose glass, aluminum, styrofoam cup, paper/cardboard cup and a plastic cup. I've found that the cardboard cup was the best followed ...
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Coffee Cup Calorimeter

Why is a magnetic stir bar important when using the coffee cup calorimeter? How is it affecting the enthalpy value? My intuition tells me that it might underestimate the true value, because the ...
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Heat of formation of silver(I) chloride

$\pu{20 mL}$ of $\pu{1.00 M}$ $\ce{NaCl}$ at $\pu{22 ^\circ C}$ is mixed with $\pu{20 mL}$ of $\pu{1.0 M}$ of $\ce{AgNO3}$ at $\pu{22 ^\circ C}$ in a calorimeter, white precipitate forms and the ...
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Bomb Calorimeter vs Cup Calorimeter

In the textbook,it is said that bomb calorimeter measures the constant volume heat ,while the cup calorimeter measure Constant pressure Heat.I was wondering, why cup calorimeter is considered constant ...
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Equations Used in Isothermal Titration Calorimetry

I have been attempting to understand and derive the formulas used for ITC which can be found here starting on page 310. I am particularly interested in the single set of identical sites. To first ...
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Calculating the heat of reaction for Mg metal and HCl

Adding $\pu{2.00g}$ $\ce{Mg}$ metal to $\pu{95.0 mL}$ of $\mathrm{1.00 M}$ $\ce{HCl}$ in a coffee-cup calorimeter leads to an increase of $\pu{9.2 ^\circ C}$. If the molar heat capacity of $\pu{1.00 M ...