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Acids and alkalis are two categories of chemicals with opposing properties, characterized by their pH levels and the ions they produce in solution. Acids have a pH less than 7 and release hydrogen ions (H+), while alkalis (also known as bases) have a pH greater than 7 and release hydroxide ions (OH-). 

Key Differences and Properties:

• Acids:

  • Have a pH less than 7.

  • Release hydrogen ions (H+) when dissolved in water.

  • Examples include hydrochloric acid, sulfuric acid, and citric acid.

  • Can neutralize alkalis.

  • Commonly used in various industries, such as manufacturing, agriculture, and food production.

    
    

• Alkalis (Bases):

  • Have a pH greater than 7.

  • Release hydroxide ions (OH-) when dissolved in water.

  • Examples include sodium hydroxide and ammonia.

  • Can neutralize acids.

  • Used in cleaning products, fertilizers, and various industrial processes.

    
    

• Neutral:

  • A pH of 7 indicates a neutral solution.

  • Neither acidic nor alkaline. 

    
    

pH Scale:

• The pH scale ranges from 0 to 14, with 7 being neutral. 

• The lower the pH, the more acidic the solution. 

• The higher the pH, the more alkaline (basic) the solution. 

• Each whole number change on the pH scale represents a tenfold change in acidity or alkalinity. 

  
  

Neutralization:

• Acids and alkalis can neutralize each other. 

• When an acid and an alkali react, they produce a salt and water. 

• For example, hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH) to produce sodium chloride (NaCl) and water (H2O). 

• Neutralization Reaction: HCl + NaOH -> NaCl + H2O. 

  
  

Corrosiveness:

• Both acids and alkalis are corrosive, meaning they can react with and "eat away" at materials they come into contact with, according to the Centers for Disease Control and Prevention (CDC).

• This includes metals, metal oxides, and even biological tissues like skin and lung tissue.