Heating and cooling curves of naphthalene

[xunxine]

When going through topics on melting and freezing, i came across 2 graphs of slightly different curvature for both the heating and cooling of naphthalene.

The ending part of the graphs are the ones that confuse me, whether slope upwards or downwards. Most graphs in the internet just show straight lines or some curve one way, some the other way.

(Pls refer to attached)
Heating curve: A or B?
Cooling curve: C or D?

Also, would the graph be similar to another substance, say stearic acid?
Thanks much!

 

[espen180]

I'd say C is the correct cooling curve, according to Wikipedia.

I think B is the correct heating curve, but don't quote me on it.

 

[xunxine]

Thanks, espen180! Those are my answers too.

But someone told me it should be A and D since they follow the shape of the curve at the beginning.

 

[espen180]

I got My answers from here:
http://en.wikipedia.org/wiki/Cooling_curve

 

[tharani]

any1 know how to toooooth!

 

[Ki@]

i did dis lab in skol... an wat i really want to know is the kinetic theory to account for the shape of the graph... can any1 pleasezz help! :-(

 

[Ki@]

ohhhhhh an in the cooling graph C is correct curve...