Which term describes a range of values used to express the concentration of hydrogen ions in a solution?

Which term describes a range of values used to express the concentration of hydrogen ions in a solution?

• A. pH scale
• B. Organic
• C. Inorganic
• D. Carbohydrates

Answer: (A)

The pH scale expresses how acidic or basic a solution is by indicating the concentration of hydrogen ions. It typically runs from about 0 to 14 at room temperature, with pH 7 being neutral; values below 7 are more acidic (higher H+), and values above 7 are more basic (lower H+). The scale is logarithmic, so each unit change represents a tenfold change in hydrogen ion concentration. For example, a drop from pH 3 to pH 2 means the solution is ten times more acidic. Other terms listed describe types of substances rather than a measure of acidity—organic and inorganic refer to categories of compounds, and carbohydrates are a type of organic compound—so they don’t describe hydrogen ion concentration.

The pH scale expresses how acidic or basic a solution is by indicating the concentration of hydrogen ions. It typically runs from about 0 to 14 at room temperature, with pH 7 being neutral; values below 7 are more acidic (higher H+), and values above 7 are more basic (lower H+). The scale is logarithmic, so each unit change represents a tenfold change in hydrogen ion concentration. For example, a drop from pH 3 to pH 2 means the solution is ten times more acidic. Other terms listed describe types of substances rather than a measure of acidity—organic and inorganic refer to categories of compounds, and carbohydrates are a type of organic compound—so they don’t describe hydrogen ion concentration.