So which of the following are chemical elements, i.e., in the periodic table of elements?  Which (if any) are fictitious?

Answer:  Brass, bronze, chrome, and steel are alloys.  Quartz is a compound.   All the rest are elements.  (In the list below, each element is followed by its number in the periodic table of elements.)  "Chrome" is a bit ambiguous.  There is an chemical element "chromium", but the shiny alloy with chromium in it is called chrome.  Krypton is a real element (#36 in the periodic table), but kryptonite is just a figment of the imagination of the author of the Superman comic books.

• aluminum (#13)
• antimony (#51)
• arsenic (#33)
• boron (#5)
• brass
• bronze
• carbon (#6)
• chrome (#24 [chromium;  see above])
• copper (#29)
• dysprosium (#66)
• einsteinium (#99)
• gold (#79)
• holmium (#67)
• iodine (#53)
• iron (#26)
• kryptonite
• mercury (#80)
• neon (#10)
• quartz
• silver (#47)
• sodium (#11)
• sulfur (#16)
• steel
• tin (#50)
• titanium (#22)
• zinc (#30)

Please feel free to suggest other substances for this list!