[Raaaaa]

I can't even pretend I have the faintest idea how to do this. Any help? See image below

Thanks in advance

[Borek]

What does Hess' law say?

Note: please read the forum rules. You have to show your attempts at answering the question/solving the problem to receive help, it is a forum policy. Stating "I have no idea" doesn't count as an attempt, you can always google for the law involved and for example problems.

[Aldebaran]

Hess's law is pretty straightforward but if you really have no idea where to start I suggest any high school text book or the following linked website as a good place to start. By the way, the website is a great resource for many other high school chemistry topics. It is well researched and written in a teach yourself style. Study the page and you should have no trouble solving the problem you posted but do come back if you get stuck having given it a go by yourself. https://www.chemguide.co.uk/physical/energetics/sums.html

[Orcio_87]

@Raaaaa - You have to add the reactions all together to calculate enthalpy of the one you want.