How much does it cost to use facebook chat for 1minute on an iphone?

Im abroad at the moment and want to use facebook chat on my iphone but its going to cost me 1 pound per mb....I don't know how many kbs it uses, using facebook chat and would like to know, so i set a time limit on how long im onlineHow much does it cost to use facebook chat for 1minute on an iphone?Assuming you turn off ALL other connections to the internet (Safari, Mail, Visual Voicemail, all Push Notifications, everything) it should only cost you one or two pounds. Leave anything else on and you could be up to 20 or 30 even if you use it for just a few minutes. It's very risky and I wouldn't recommend it.How much does it cost to use facebook chat for 1minute on an iphone?when u say 1 or 2 pounds, how long is that for??....1 or 2 pound for the entire duration?? for an hour??