thank you lzxnl
can you please help me: Suggest why salt is included in the contents of the bag.
please see attachment
It's a redox reaction => electrons need to flow. Dissolved salts increase the conductivity of the solution and thus speed up redox reactions.
hello everyone !!!
i have a question:
why is it necessary to calibrate a calorimeter? don't you have to do it every time you are about to begin the experiment to calculate the heat of reaction, you can't just start it on one day and then finish it off on the next day using the same calibration factor... you have to do it all over again???
something about heat released in absorbed by instrument? how does that affect?
I'm doing the prac next week
thank you
Well...you want an accurate result from your calorimeter and anything can affect its accuracy, including its temperature (like if it was used before), whether or not the instrument has been affected by heat etc. Basically you recalibrate it to be safe.
Hi guys,
If a question asks for the combustion reaction of maltose, how do you know that maltose is (s)? Couldn't it also be (aq)? VCAA 2007, exam 2, q4aii only allows for (s).
You're burning it. I dunno why you'd be burning something aqueous as you'd be heating the water as well; not awfully efficient
Calculate the energy absorbed when 2.00 g of NH4Cl is
dissolved in:
i 100 mL water ii 1000 mL water
- find mols
-use delta H and the reaction equation...
i get how to do the question but the worked solutions says: The amount of energy absorbed does not depend on the volume of the solution?
why is that?
i know that changing the volume changes the concerntration of the solution because there is a constant 2g of NH4Cl is each solution... wouldn't the less concerntrated absorb less? i'm not sure... please clarify
The concentration of the solution has no bearing on how much energy is released. The amount of energy released is really only dependent on the number of moles of reactant, not the concentration of reactant.
What WILL change is the temperature change as then there's more water to absorb the energy released. The energy release doesn't change.