Will jailbreaking an iphone 5 make it slower?

Will it make it slower and can i jailbreak it get a few tweaks and unjailbreak it and have the tweakes

Depends
Pro only but not much

Yup it depends if your an idiot and don't know how to use a jailbreak then mostlikely it will be slower but if you know how to use it then no.

Nope. It will work fine. I've done it with all of my devices. If you want to jailbreak the right way, here's a step by step tutorial on how to do it:

Here are some cool things you can download once you're jailbroken:

Hope this helps you out!

Yes all jailbreaks slow down all iphones, but its not really noticeable in the iphone 5

Yes, it does.