Question

What is true of a solution that goes from pH 5 to \(\mathrm{pH} 8 ?\) a. The \(\mathrm{H}^{+}\) concentration decreases as the solution becomes more basic. b. The \(\mathrm{H}^{+}\) concentration increases as the solution becomes more acidic. c. The \(\mathrm{H}^{+}\) concentration decreases as the solution becomes more acidic.

Short answer

The correct statement for a solution that goes from pH 5 to pH 8 is: a. The H+ concentration decreases as the solution becomes more basic.

Step-by-step solution

Understand the relationship between pH and H+ concentration

Recall that the pH of a solution is a measure of its acidity or alkalinity. Mathematically, it's represented by the following equation: \[ \mathrm{pH} = -\log{[\mathrm{H}^+]} \] where \( [\mathrm{H}^+] \) is the concentration of H+ ions in the solution. When the pH of a solution increases, its H+ concentration decreases, and the solution becomes less acidic (or more basic). Conversely, when the pH of a solution decreases, its H+ concentration increases, and the solution becomes more acidic (or less basic).

Analyze the statements given

Let's evaluate each statement in the light of the relationship between pH and H+ concentration: a. The H+ concentration decreases as the solution becomes more basic. b. The H+ concentration increases as the solution becomes more acidic. c. The H+ concentration decreases as the solution becomes more acidic.

Determine the True Statement

We are given that the pH increases from 5 to 8. This means that the solution becomes more basic. Based on the relationship between pH and H+ concentration, when the solution becomes more basic, the concentration of H+ ions decreases. This matches with statement (a): a. The H+ concentration decreases as the solution becomes more basic. The correct statement that is true for a solution that goes from pH 5 to pH 8 is: a. The H+ concentration decreases as the solution becomes more basic.

Key concepts

pH scale

The pH scale is a handy tool to measure how acidic or basic a solution is. It ranges from 0 to 14, with 7 being neutral. Everything below 7 indicates an acidic solution, while anything above 7 is basic.

The pH scale is very intuitive:

• 0-6: Acidic
• 7: Neutral
• 8-14: Basic

Understanding where a solution falls on this scale helps us know its properties and how it might react with other substances. For instance, a solution changing from pH 5 to pH 8 moves from being slightly acidic to basic.

H+ concentration

H+ concentration plays a crucial role in determining a solution's pH. The concentration of hydrogen ions is inversely related to the pH value.

When the H+ concentration is high, the solution is more acidic, leading to a lower pH number. Conversely, if the H+ concentration is low, the solution becomes more basic, resulting in a higher pH value. This relationship is key to understanding how changes in pH reflect changes in the solution's acidity or basicity.

acidic and basic solutions

Acidic and basic solutions have distinct characteristics. Acidic solutions, with a pH less than 7, have a higher concentration of H+ ions, making them more corrosive and reactive.

Basic solutions, on the other hand, have a pH greater than 7 and contain fewer H+ ions, often resulting in a slippery feel and a bitter taste.

• Acidic solutions: Higher H+ concentration, more reactive.
• Basic solutions: Lower H+ concentration, less reactive.

These properties are crucial for chemical reactions and biological processes.

logarithmic scale

The pH scale is a logarithmic scale, which means each whole pH value represents a tenfold difference in H+ concentration.

For example, a solution with a pH of 5 has ten times more H+ ions than a solution with a pH of 6. This logarithmic nature helps express a wide range of H+ concentrations in a simple, compact way.

Understanding this concept is vital, as even small changes in pH can lead to significant shifts in a solution's behavior and properties.