Sodium hydroxide -LRB- lye -RRB- is used in industry as a strong base , potassium hydroxide is used in agriculture , and iron hydroxide minerals such as goethite and limonite have been used as low grade brown iron ore .

Sodium hydroxide is used in industry as a strong base , potassium hydroxide is used in agriculture , and iron hydroxide minerals such as goethite and limonite have been used as iron ore .
