Introduction to Acids and Bases In GCSE Chemistry, understanding acids, bases, and their reactions is crucial. Acids and bases play a vital role in many chemica...
In GCSE Chemistry, understanding acids, bases, and their reactions is crucial. Acids and bases play a vital role in many chemical processes and have numerous applications in daily life.
Acids are substances that release hydrogen ions (H+) when dissolved in water. Common examples include hydrochloric acid (HCl), sulfuric acid (H2SO4), and nitric acid (HNO3). Acids have the following properties:
Bases, also known as alkalis, are substances that release hydroxide ions (OH-) when dissolved in water. Examples include sodium hydroxide (NaOH), potassium hydroxide (KOH), and ammonia solution (NH3). Bases have the following properties:
The pH scale measures the acidity or basicity of a solution. It ranges from 0 to 14, with values below 7 indicating an acidic solution, 7 being neutral, and values above 7 indicating a basic solution. The pH value is related to the concentration of hydrogen ions (H+) in the solution.
Problem: Calculate the pH of a solution with a hydrogen ion concentration of 1.0 × 10-5 mol/L.
Solution:
Neutralization is the reaction between an acid and a base, forming a salt and water. The general equation for neutralization is:
Acid + Base → Salt + Water
For example, when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH), the products are sodium chloride (NaCl) and water (H2O):
HCl + NaOH → NaCl + H2O
Titrations are laboratory techniques used to determine the concentration of an unknown solution by reacting it with a known solution of the opposite type (acid or base). The point at which the two solutions neutralize each other is called the equivalence point, which can be detected using indicators or pH meters.