Question

1. define the following terms

a. acid
b. base
c. ph

Explanation:

• a. Acid: A substance that donates hydrogen ions (\(H^{+}\)) in a solution. For example, hydrochloric acid (\(HCl\)) dissociates in water as \(HCl

ightarrow H^{+}+Cl^{-}\).

• b. Base: A substance that donates hydroxide ions (\(OH^{-}\)) in a solution (Arrhenius definition) or accepts hydrogen ions (\(H^{+}\)) (Bronsted - Lowry definition). For example, sodium hydroxide (\(NaOH\)) dissociates as \(NaOH

ightarrow Na^{+}+OH^{-}\), and ammonia (\(NH_{3}\)) can act as a base by accepting \(H^{+}\) (\(NH_{3}+H^{+}
ightarrow NH_{4}^{+}\)).

• c. pH: A measure of the acidity or alkalinity of a solution. It is defined as \(pH =-\log[H^{+}]\), where \([H^{+}]\) is the hydrogen ion concentration in moles per liter. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

Answer:

a. A substance that donates hydrogen ions (\(H^{+}\)) in a solution.
b. A substance that donates hydroxide ions (\(OH^{-}\)) (Arrhenius) or accepts hydrogen ions (\(H^{+}\)) (Bronsted - Lowry).
c. A measure of the acidity or alkalinity of a solution, defined as \(pH =-\log[H^{+}]\).