Q.14 a) Calculate the percentage of nitrogen in the four important compounds (1)i) NH2CONH4 urea)
(

The reaction will shift to the right

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.

The answer is b because c don't explain why the moths are on them and it isn't a because as we know only one species of moth does this