8.2 pH and pOH of Strong Acids and Bases

• Weak acids and bases only partially dissociate in water
• Match the property with the correct type of acid or base:

  Dissociation is complete ↔️ Strong acids/bases

  pH is moderate ↔️ Weak acids/bases

  Concentration of H+ is high ↔️ Strong acids
• What ions do strong acids completely dissociate into in water?

  Hydrogen ions (H+)
• What is an example of a strong acid?

  Hydrochloric acid (HCl)
• What is the dissociation of strong acids in water called?

  Complete dissociation
• What is the definition of pH?

  $pH =$$- \log[H^ + ]$
• What type of pH and pOH values do strong acids and bases have?

  Extreme
• The relationship between pH and pOH is always pH + pOH = 14</latex> at 25°C.


  True
• Order the following solutions from lowest to highest pH:

  1️⃣ Strong acid

  2️⃣ Weak acid

  3️⃣ Weak base

  4️⃣ Strong base
• Strong acids and bases have extreme values of pH and pOH.


  True
• The concentration of H+ or OH- in weak acids and bases is low.


  True
• What is the formula for calculating pH?

  $pH =$$- \log[H^ + ]$
• For strong acids, what is the concentration of H+ ions equal to?

  Molarity of the acid
• What is the definition of pH in terms of hydrogen ion concentration?

  $pH =$$- \log[H^ + ]$
• Weak acids and bases have a high concentration of H+ or OH- ions.

  False
• What type of pH/pOH values do weak acids and bases have?

  Moderate
• Weak acids and bases have a low concentration of H+ or OH- ions.


  True
• For strong acids, the concentration of H+ ions is equal to the molarity of the acid.
• For strong acids, the pH is solely determined by the concentration of H+ ions.


  True
• Steps to calculate the pOH of a strong base

  1️⃣ Determine the molarity of the base

  2️⃣ Since strong bases completely dissociate, [OH-] equals the molarity

  3️⃣ Substitute the [OH-] value into the pOH formula
• Strong bases completely dissociate into hydroxide ions (OH-) in water.


  True
• What is an example of a strong base?

  Sodium hydroxide (NaOH)
• Strong acids and bases have extreme pH or pOH values.


  True
• pOH is a measure of the concentration of hydroxide ions (OH-) in a solution.


  True
• What type of pH and pOH values do weak acids and bases have?

  Moderate
• The formula for pH is $pH =$$- \log[H^ + ]$
• Strong acids and bases have pH values close to 0 or 14.


  True
• The concentration of H+ or OH- in strong acids and bases is high
• What do strong acids dissociate into in water?

  Hydrogen ions (H+)
• What is the formula for calculating pOH?

  $pOH =$$- \log[OH^ - ]$
• pH is solely determined by the concentration of H+ ions.


  True
• What is the relationship between pH and pOH at 25°C?

  $pH +$$pOH =$$14$
• The relationship between pH and pOH is given by the equation pH + pOH = 14.
• The sum of pH and pOH is always equal to 14.
• Weak acids and bases have moderate pH and pOH values.


  True
• What is the formula to calculate pH from the concentration of H+ ions?

  $pH =$$- \log[H^ + ]$
• The pOH of a solution measures its alkalinity.
• What are two effects of pH and pOH on chemical reactions?

  Reaction rates and equilibrium
• Weak acids and bases dissociate only partially
• The relationship between pH and pOH is $pH +$$pOH =$$14$