Possible Clues:

• Sodium hydroxide, to chemists
• Caustic soda, chemically
• Sodium hydroxide, to a chemist
• Chemical formula for lye
• Sodium hydroxide, chemically
• Sodium hydroxide, in chem class
• Sodium hydroxide, in lab shorthand
• Lye, in a lab
• Soda, symbolically
• Sodium hydroxide, symbolically