[timchai]

i want to ask sketch a graph of variation in temperature with time as the liquid alkane is heated to
well above its boiling point. why ans said the temperature first increase linearly and then remain contant , and then increase linearly

[Astrokel]

I believe your only problem is why it remain constant in between. What happens as liquid alkane being heat to boiling point?

p.s.: There is no need to set up a poll.

[cliverlong]

i want to ask sketch a graph of variation in temperature with time as the liquid alkane is heated to
well above its boiling point. why ans said the temperature first increase linearly and then remain contant , and then increase linearly

Have you studied in class phase changes? What do you understand by phase change? I would have expressed the question as the alkane is heated from below its melting point to above its boiling point. I don't think it is relevant the chemical is an alkane. I don't think it is relevant that the question says the liquid alkane is heated to well above its boiling point (I might be wrong)

Here is a simple introduction to relevant    information

http://bhs.smuhsd.org/science-dept/marcan/apchemistry/cool_phase_changes_explain.html

Clive

[Borek]

I don't think it is relevant the chemical is an alkane. I don't think it is relevant that the question says the liquid alkane is heated to well above its boiling point (I might be wrong)

And surely you are

Latent heat.

[cliverlong]

I don't think it is relevant the chemical is an alkane. I don't think it is relevant that the question says the liquid alkane is heated to well above its boiling point (I might be wrong)

And surely you are

Latent heat.

Sorry I don't get it.

The latent heat is the energy absorbed or released when a substance changes its state but does not change its temperature (for example ice melting to water)

The question says says the liquid alkane is heated to well above its boiling point  and I don't get where latent heat comes into that situation because there is no change of state.


Thanks

Clive

[Astrokel]

There is a change of state. Liquid alkane heated above its boiling point. It has become a gas once it reaches above boiling point.

[cliverlong]

There is a change of state. Liquid alkane heated above its boiling point. It has become a gas once it reaches above boiling point.

The point is the question says well above its boiling point. Note well above. This means the temperature range is well outside one where there is a change of state and latent heat isn't part of the behaviour (from my reading of the original question).

Clive

[Astrokel]

Well above its boiling point basically means it has become a gaseous alkane. From liquid to gaseous alkane, it must undergo latent heat of vaporization, otherwise it will never be gaseous.

liquid alkane is heated to well above its boiling point.

I think you have different understanding on the question phrasing. It actually meant it heats from the alkane in liquid and to gaseous and continue further heating. At least, that is what i intepreted.

[Borek]

And you are not alone in your interpretation