Why Are pH Values Only In A Range Of 0-14?

The video tutorial explains the pH scale, which ranges from 1 to 14, with 7 being neutral. It describes how values below 7 indicate acidity and values above 7 indicate alkalinity. The pH scale is logarithmic, meaning each unit change represents a tenfold change in acidity or alkalinity. The concept of pH was introduced by Soren Peter Lauritz, and it measures the hydrogen ion concentration. Although theoretically, pH can range from negative to positive infinity, practical measurements are usually between 0 and 14. Extreme pH values are difficult to measure accurately due to limitations in instruments. The video concludes by emphasizing the importance of pH in chemistry and the need for improved measurement techniques.

What does a pH value below 7 indicate about a substance?

• It is neutral.

• It is acidic.

• It is non-reactive.

• It is alkaline.

How much more acidic is a substance with a pH of 3 compared to one with a pH of 5?

• Thousand times more acidic

• Twice as acidic

• Ten times more acidic

• Hundred times more acidic

Who introduced the concept of pH?

• Dmitri Mendeleev

• Albert Einstein

• Marie Curie

• Soren Peter Lauritz Sorensen

Why is it difficult to measure pH values below 0 or above 14?

• Because they require extremely acidic or basic solutions

• Because they are not possible to achieve

• Because they are not defined in the pH scale

• Because they are not relevant in chemistry

What is a major limitation of pH meters when measuring extreme pH values?

• They cannot measure pH above 7

• They are not accurate due to acid error

• They are too expensive

• They require a lot of maintenance