Solids:

1. Salt (Sodium Chloride) - A common table salt

2. Sugar (Sucrose) - A sweet, white crystalline substance

3. Baking Soda (Sodium Bicarbonate) - A common ingredient in baking

4. Citric Acid - Found in citrus fruits

5. Potassium Permanganate - A strong oxidizing agent

6. Copper Sulfate - Used in agricultural fungicides

7. Epsom Salt (Magnesium Sulfate) - Often used for baths and gardening

8. Borax (Sodium Borate) - Used in laundry detergents and cleaning solutions

9. Alum (Potassium Aluminum Sulfate) - Used in water treatment and food processing

10. Glycine - An amino acid

11. Caffeine - A stimulant found in coffee and tea

Liquids:

12. Alcohol (Ethanol) - A common ingredient in alcoholic beverages

13. Vinegar (Acetic Acid) - A common household ingredient

14. Hydrogen Peroxide - A disinfectant and bleaching agent

15. Glycerol - A thick, sweet liquid used in cosmetics and pharmaceuticals

Gases:

16. Carbon Dioxide - A gas that dissolves to form carbonic acid

17. Oxygen - Essential for respiration

18. Ammonia - A pungent gas used in cleaning products

19. Sulfur Dioxide - A gas that dissolves to form sulfurous acid

Other:

20. Soap - Contains detergents that dissolve in water to help remove dirt

Note: The degree of solubility varies for each substance. Some substances dissolve very easily in water, while others only dissolve slightly.