Welcome to Mac-Forums..
This is the USB Apple Keyboard with the numeric keyboard. It should just work without any problems as long as your USB port works.
What Mac do you have? What about the keyboard doesn't work? Have you tried this keyboard on all/other ports and computers?
Have you used this keyboard on other computers?
MBA, The Yosemite recognize the keyboard , the hub on keyboard works fine but the keys do not .
What year and model MacBook Air do you have? And is this a new Apple aluminum keyboard or is it an older model? The reason for the questions is that there are two different models of the Apple aluminum keyboard. One model works with just about every Mac, the other only works with newer Macs.
It does sound like the aluminum keyboard you have is an older model and may not work properly on your MacBook Air. There was a firmware update for older model aluminum keyboards that you might try. Let me see if I can find it.... Sorry, that firmware update is no longer available from Apple. The only updates are for the wireless keyboards.
How old is the aluminum keyboard and where did you get if from? Maybe we can figure out the model that way.
Is from 2013, its Portuguese.