Initial Letters Quiz Puzzle Answer

The nine questions below have one-word answers - the answer to question three is hyphenated. The first letters of the nine answers in question order spell out a topical word, phrase or saying. What is it?

1. Which App and Website has a logo of a white letter F on a blue background?
   
2. In which country does Balsamic Vinegar originate?
   
3. Of which band were Joseph Simmons and Darryl McDaniels members, the name is from the former's nickname and letters from the latter's name?
   
4. Which part of the body is affected by Conjunctivitis?
   
5. In which Rihanna song does she say the one-word title 79 times?
   
6. Founded in 1096, what is the oldest University in England?
   
7. What is the main alcoholic drink used in a Zombie cocktail?
   
8. What Japanese word means Empty Orchestra?
   
9. What is the only rock regularly eaten by humans?
   

The answers are:

1. Facebook
2. Italy
3. Run-DMC
4. Eyes
5. Work
6. Oxford
7. Rum
8. Karaoke
9. Salt

And the word is FIREWORKS