Sodium Hydroxide

Definition

Sodium hydroxide, also known as caustic soda or lye, is a highly alkaline chemical compound with the formula NaOH. It is a white, crystalline solid that is widely used in various industrial and household applications due to its strong base properties.

5 Must Know Facts For Your Next Test

1. Sodium hydroxide is a strong base that readily dissociates in water to form hydroxide ions (OH-), making it highly alkaline.
2. It is commonly used in the production of soap, paper, textiles, and detergents, as well as in the treatment of wastewater and the manufacture of other chemicals.
3. Sodium hydroxide is a key reagent in acid-base titrations, where it is used to neutralize acids and determine their concentration.
4. The high pH of sodium hydroxide solutions makes them effective for cleaning and degreasing, as well as for adjusting the pH of solutions.
5. Sodium hydroxide is a corrosive substance and must be handled with caution, as it can cause severe burns and eye damage upon contact.

Review Questions

• Explain how the strong base properties of sodium hydroxide make it useful in classifying chemical reactions.
  • As a strong base, sodium hydroxide readily dissociates in water to produce a high concentration of hydroxide ions (OH-). This allows it to participate in acid-base reactions, where it can neutralize acids by accepting protons (H+) to form water and a salt. The ability of sodium hydroxide to act as a strong base is a key factor in its use for classifying chemical reactions, such as identifying acid-base, precipitation, and neutralization reactions.
• Describe the role of sodium hydroxide in acid-base titrations and how it can be used to determine the concentration of an unknown acid solution.
  • Sodium hydroxide is a common titrant used in acid-base titrations to determine the concentration of an unknown acid solution. In a titration, a standard solution of sodium hydroxide with a known concentration is slowly added to the unknown acid solution until the reaction is complete, as indicated by a change in pH or the appearance of a color indicator. By monitoring the volume of sodium hydroxide required to reach the endpoint of the titration, the concentration of the unknown acid can be calculated using the stoichiometric relationship between the acid and the base.
• Analyze the importance of considering the strong base properties of sodium hydroxide when using it in various applications, such as in the production of soap or the treatment of wastewater.
  • The strong base properties of sodium hydroxide are crucial in many of its applications. In soap production, the high pH of sodium hydroxide solutions allows it to effectively saponify fats and oils, converting them into soap molecules. Similarly, in wastewater treatment, the alkaline nature of sodium hydroxide can be used to adjust the pH of the water, neutralizing acidic components and facilitating the removal of contaminants. However, the corrosive and hazardous nature of sodium hydroxide must also be carefully considered when handling and using it, as improper use can lead to severe damage to equipment, the environment, and human health.

Related terms

Acid-Base Reactions: Reactions between acids and bases that result in the formation of a salt and water. Sodium hydroxide is a strong base that can participate in these reactions.

pH Scale: A scale that measures the acidity or basicity of a solution, with 7 being neutral. Sodium hydroxide is a highly basic compound, with a pH greater than 7.

Titration: A laboratory technique used to determine the concentration of an unknown solution by slowly adding a standard solution of known concentration until the reaction is complete, as in acid-base titrations.