Properties of Acids and Bases:

1. Acids:
- Acids are substances that release hydrogen ions (H+) when dissolved in water.
- They have a sour taste and can react with metals to produce hydrogen gas.
- Acids turn blue litmus paper red, indicating their acidic nature.
- Examples of acids include hydrochloric acid (HCl) and sulfuric acid (H2SO4).

2. Bases:
- Bases are substances that release hydroxide ions (OH-) when dissolved in water.
- They have a bitter taste and feel slippery to the touch.
- Bases turn red litmus paper blue, indicating their basic nature.
- Examples of bases include sodium hydroxide (NaOH) and potassium hydroxide (KOH).

3. Strength:
- Acids and bases can be classified as strong or weak based on their ability to dissociate in water.
- Strong acids completely dissociate into ions in water, while weak acids only partially dissociate.
- Strong bases fully dissociate into hydroxide ions, while weak bases do not dissociate completely.

4. pH Level:
- Acids have a pH level below 7, with lower pH values indicating stronger acidity.
- Bases have a pH level above 7, with higher pH values indicating stronger basicity.
- The pH scale ranges from 0 to 14, with 7 being neutral (neither acidic nor basic).
- The concentration of hydrogen ions determines the pH level of a solution: the higher the concentration, the lower the pH (more acidic), and vice versa.