I think it converts electrical energy to sound energy because, say if you're listening to music on your phone but, with the speaker on. The speaker of the phone on the other end changes the electrical energy/ electromagnetic waves back into sound energy. I believe the same goes with headphones
Nitrogen can make bonds with other atoms.. Typically though it only makes 3 bonds, so it fills its octet.
Answer:
double replacement
synthesis
double replacement
i think this one is decomposition
synthesis
double replacement
single replacement
single replacement
double replacement
single replacement .....
hopefully i help