PhET Acid-Base Solutions: dissociation, pH and electrolytes

If "HA" represents a strong acid, what do you think A- represents?

• A- represents a weak acid compound.
• A- represents the negative ion that remains after the H+ from the acid is "donated" to the solution.

• A- represents a neutral compound.
• A- represents a strong acid.

In water, a few particles dissociate into OH^- and H₃O⁺ ions, and yet the pH remains neutral. Why?

(Remember, H₃O⁺ (Hydronium) ions form when an acid "donates" an H⁺ ion and it combines with water)

• The pH is neutral because there are no ions present.
• The pH remains neutral due to the presence of only H2O molecules.
• The pH is neutral because the temperature of the water is constant.
• The pH remains neutral because the concentrations of H3O+ and OH- ions are equal.

What does a strong acid do in terms of dissociation?

• A strong acid does not dissociate at all in solution and instead forms a precipitate.

• A strong acid only dissociates in high concentrations.
• A strong acid partially dissociates in solution.
• A strong acid fully dissociates in solution.

How can you identify a weak acid in the simulation?

• A weak acid has a high pH value.
• A weak acid reacts vigorously with metals.
• A weak acid partially ionizes in solution.
• A weak acid completely ionizes in solution.

What methods can you use to measure the pH of a solution?

• Observing color or clarity
• Measuring mass or volume
• Measuring density or electrical conductivity
• Using acid base-indicators such as litmus or pH meters

How many times more hydroxide ions does the strong base (pH 12) contain than water (pH 7)?

• 1000
• 100000
• 1000000000
• 10000000

What do you think would give you a more accurate pH reading, the pH meter, or the indicator?

What does pH measure?

• Amount of Oxygen Ions
• Amount of Hydrogen Ions
• The amount of salt in a solution
• The density

What is the significance of the pH scale in the simulation?

• The pH scale is significant as it indicates the acidity or alkalinity of a solution

• The pH scale indicates the density of a solution.
• The pH scale is used to determine the color of a solution.
• The pH scale measures temperature changes in a solution.

What pH is considered neutral?

• 7
• 5
• 14

• 0