In the equations you provided, it appears that you're working with acetic acid (C₃H₆O₄H or CH₃COOH) and various bases. Here are the balanced reactions:

1. **C₃H₆O₄H + K₂O → 2 KCH₃COO**
- **Products:** 2 moles of potassium acetate (KCH₃COO)

2. **C₃H₆O₄H + NaOH → CH₃COONa + H₂O**
- **Products:** Sodium acetate (CH₃COONa) and water (H₂O)

3. **C₃H₆O₄H + ? → ? + H₂O**
- Assuming a reaction with a carbonate, for instance:
- **C₃H₆O₄H + CaCO₃ → Ca(CH₃COO)₂ + CO₂ + H₂O**
- **Products:** Calcium acetate (Ca(CH₃COO)₂), carbon dioxide (CO₂), and water (H₂O)

Based on this information, you can replace the "?" with the appropriate reactants and products in your equations. If you provide further details or specific reactants you’d like to use, I can assist more accurately.