AS Chemistry Unit 3B Edexcel IAL 2015 Discussion

What did you guys answer, why we can't measure the ∆H for the thermal decomposition of NH4Cl?

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carboxylic acids and alcohols. I said dehydrating agent removes an OH group which is bonded whereas a drying agent just removes water from the solution.

It was a tertiary alcohol though

My friends said temperature change of heating process cannot be measured.

That one is always dodgy for me... I said since the products are gases they would escape so energy will leave the system.

I wrote the skeletal formula for 1,2-dibromocyclohexane instead of didplayed formula!!!
and anyone knows why glass wool is better than filter paper? I wrote less transfer loss as filter paper absorbs the product.

For drying agent, I wrote to remove water from a mixture...

Oh, I guess he/she is right, I didn't know what to write so I wrote because ∆H is very low

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I wrote that but I crossed it out, Idk why though I just thought that the answer is wrongPosted from TSR Mobile

I wrote coz the products are gases. Temperature of gases are hard to measure.
Well, it just costs 1 mark,I think it won't affect the grade,haha.

Same I wrote because filter paper absorbs some of the product decreasing the percentage yield

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I wrote coz the products are gases. Temperature of gases are hard to measure.
Well, it just costs 1 mark,I think it won't affect the grade,haha.

I wrote the skeletal formula for 1,2-dibromocyclohexane instead of didplayed formula!!!
and anyone knows why glass wool is better than filter paper? I wrote less transfer loss as filter paper absorbs the product.

For drying agent, I wrote to remove water from a mixture...

I literally wrote the exact same thing for filter paper! Yayy!!

For the e=mct did you use 25 or 30 grams for mass?
How did your Hess cycle look like?

For the e=mct did you use 25 or 30 grams for mass?
How did your Hess cycle look like?