Can I use the USB to wall adapter of an old iPhone for the iPhone 5?

I have an old USB adapter which allowed me to charge my old iPhone 3gs with my USB cable through the mains. I just bought a second hand iPhone 5 and I didn't get the wall adapter with it. Can I use the wall adapter from the 3gs with the iPhone 5's lighting port cable thingy?

Problems downloading iPhone app?

So I tried downloading tumblr on my iPhone 4 only to find out that the new update requires ios 8 which doesn't support my iPhone._. Does anyone know of any ways around this or something?

Delete already imported from iphoto photos on iphone?

So, before I imported a bunch of photos from my iphoto to my iphone. Then after that i reseted my macbook pro which deleted everything but those photos were still on my iphone. I erased and synced everything from my updated mac, but the photos are still there, i tried deleting them, but they don't give me the option to. Also, i would like to know how to delete them, if you say hide them, please tell me a different way then cropping it since i tried that already, and it didn't work. Please help, its taking up so much of my iphone space!