MCQ Detailed View

The pH scale is a standard scale ranging from 0 to 14 that measures the acidity or alkalinity of a solution. A solution with a pH value less than 7 is considered acidic, a solution with a pH value of exactly 7 is neutral, and values greater than 7 indicate alkalinity. The acidic range on the pH scale extends from 1 to 6.

Acidity is determined by the concentration of hydrogen ions (H⁺) in the solution. The lower the pH, the higher the hydrogen ion concentration, and therefore the stronger the acid. For example, hydrochloric acid (HCl) in solution can have a pH close to 1, which represents a strong acid. Vinegar, which contains acetic acid, typically has a pH around 3, while lemon juice has a pH of about 2.

Weak acids usually fall in the upper part of the acidic range, between pH 4 and 6, while strong acids are found at the lower end of the scale, between pH 1 and 3. The pH scale is logarithmic, which means that each step represents a tenfold change in hydrogen ion concentration. This makes pH measurement a sensitive method for distinguishing between different strengths of acids.

The neutral point of the scale, pH 7, corresponds to pure water at 25°C. Any solution with a pH below this neutral value is classified as acidic. This classification is used in analytical chemistry, environmental monitoring, food chemistry, and biological systems.

In laboratory analysis, determining whether a solution is within the acidic range is essential for titrations, buffer preparation, and quality testing. Acidic solutions play important roles in digestion, industrial cleaning, and many chemical processes.

Thus, the acidic pH range on the pH scale is from 1 to 6, which covers both weak and strong acids.