[curiouscat]

What's the MW of C6H5NH2?  You will need it.

If ΔHrxn=qrxn and q= C*ΔT, then C =j/°c and q=j. Then doesn't ΔH = j instead of J/moles?

You are confusing people by using non standard notation. Joules ≡ J and never j.

Even better practice is to always define your notation.

[curiouscat]

The K is actually a lower case k but I don't think that is the confusion.

It may not be the confusion in this case, yet get into the habit of doing notation right. Notation is important.

Kilo- (symbol: k, lowercase)

Always kJ and never KJ

[anujfr]

What is the "right" answer?

The right answer is 6.84 kJ/°C

What's the MW of C6H5NH2?  You will need it.

What is MW??

[Borek]

Molecular Weight, or Molar Weight.

[anujfr]

Sorry but I am confused. Do you want the Molecular mass * 9.8 or just the mass. I am confused because you said weight which is mass * acceleration due to gravity.

[curiouscat]

Sorry but I am confused. Do you want the Molecular mass * 9.8 or just the mass. I am confused because you said weight which is mass * acceleration due to gravity.

Why don't you think about it a bit? Have you seem Molecular Mass * 9.8 being used in a ThermoChem Context?

Even better if you are so wracked by doubt report both.  My point is let's start doing some number crunching.