Related Clues:

• Heartburn cause
• Base antagonist?
• Beyond sarcastic
• See 43 Across
• Part of RNA
• Sulphuric or nitric
• Boric, e.g.
• Low-pH substance
• Sour-tasting substance
• Carbolic and sulphuric ender
• Base neutralizer
• Scathing
• Target of milk of magnesia
• It turns litmus paper red
• The ''A'' in DNA