Question

1. For each pH listed below indicate if it is acid, base, or neutral (0.5 pts)
   1. pH 4
   2. pH 7
   3. pH 10

Answer 1

The pH scale is used to measure the potential Hydrogen i.e. how much hydrogen ion (H+) concentration is present in the substance in relation to hydroxide ions (OH​​​-). Higher hydrogen ion concentration means it is acidic and lesser hydrogen ion concentration means it is basic. The scale ranges from 0 to 14. Based on this measure, a

A pH of 7 is neutral (equal concentration of H+ and OH​​​​​- ions)

A pH lesser than 7 is acidic (greater concentration of H+ than OH​​​​​- ions)

pH higher than 7 is base. (Lesser concentration of H+ than OH​​​​​- ions)

Therefore,

a. A pH of 4 is acidic since it is lower than 7. An example would be tomato juice.

b. A pH of 7 is neutral. pH 7 means that the number of hydrogen ions and hydroxide ions are in equal concentration so it cannot be a base nor can it be an acid. Eg. Water.

c. A pH of 10 is base since it is higher than 7. For example, Milk of magnesia