can you please explain the distinction between compound word and collocation

Answer 1

A compound word is one word made up of two other words. Examples:

bedroom
Facebook
baseball
fireworks
cannot

http://www.learningdifferences.com/Main%20Page/Topics/Compound%20Word%20Lists/Compound_Word_%20Lists_complete.htm

A collocation is two words that are often used together.

http://www.learningdifferences.com/Main%20Page/Topics/Compound%20Word%20Lists/Compound_Word_%20Lists_complete.htm

http://www.englishclub.com/vocabulary/collocations.htm