Related Clues:

• Part of DNA
• 91-Across, e.g.
• Etcher's purchase
• Type of blocker
• Alpha chaser
• Low pH
• Sulfuric or hydrochloric follower
• Type of rain
• Corrosive chemical
• See 48 Across
• ___ testing
• Dropped stuff
• Car battery component
• Cause of some bellyaching
• Corrosive compound