Yet another quiz puzzle! [Ended, answers posted]

Here.
This puzzle is a fraternal twin of my previous puzzle.

I'm going to use some formatting suggestions by adamofgreyskull this time.

Game: Finding that out is the part of the quiz.
Contributor: $0.99
Star time: Jun 8, 2012 11:00 a.m. GMT+4
End time: Jun 12, 2012 11:00 a.m. GMT+4
Help: www.google.com

Entries: 32

Hints:
2) "The other thing" is a dental hygiene product.
5) Take a closer look at my profile.

Answers:
1) mercury (also hydrargyrum, quicksilver or Hg)
The only metal liquid at room temperature.
2) orange juice

• toothpaste = really bad taste in your mouth.
  3) blood (also кровь or Blut)
  This proverb.
  4) water (aka dihydrogen monoxide)
  I copy-pasted description from here almost completely.
  5) Vessel
  And the hints was about communicating vessels.

Just like in the previous puzzle there was a second giveaway with Batman game. This time it was Arkham City. The description had base64 code which when decoded (with this for example) gave you the link to another quiz. You had to recognise actors who portrayed Batman. Answers: 1) Val Kilmer 2) Kevin Conroy 3) George Clooney 4) Adam West 5) Christian Bale 6) Michael Keaton. In the next quiz you had to recognise actors who portrayed Joker. Answers: 1) Mark Hamill 2) Cesar Romero 3) Heath Ledger 4) Jack Nicholson. And the answer to final question was "echolocation" (since that's what bats use for navigating).
After that you were finally given link to Arkham City DLC - Harley Quinn's Revenge.