Titrations

The equivalence point is the

• theoretical halfway point of the reaction

• empirically derived completion of the reaction using phenolphthalein

• theoretical completion of the reaction

• the actual measurement based on the presence of the indicator

What makes KHP a primary standard?

• available in highly pure crystals

• highly stable and can be dried of atmospheric moisture

• reacts precisely and reproducibly

• can be precisely massed and molecular mass known

• all of the above

In addition to neutralization, what other class of reaction occurs between KHP and NaOH solutions?

• combustion

• double replacement

• single replacement

• composition

If NaOH solution added to a solution at physiological pH raises the pH to the phenolphthalein end point (around pH 8.35), the acidity of the solution has

• increased 10x

• decreased 1x

• decreased 10x

• increased 1x

What is the impact of adding small volume of water to the KHP in the Erlenmeyer in Part A?

• dilutes KHP so less base solution required to neutralize

• need to add a lil bit more KHP to even things out

• must redo titration

• no impact; only need approximate KHP solution volume for Part A

Tags

NGSS.HS-PS1-5

If the Erlenmeyer flask contains acidic solution and a few drops of phenolphthalein, its color will be

• pink

• blue

• red

• colorless

What is the reading on this burette?

• 4.40mL

• 3.50mL

• 3.60mL

• 4.50mL

A titration works by using a ___________________________ reaction.

• Single Replacement

• Neutralization

• Combustion

• Synthesis

Why do we perform a titration?

• To determine the concentration of an unknown solution

• To see if a reaction will occur between an acid and base

• To find the mass of an unknown acid

• To find the molar mass of an unknown solution

Tags

NGSS.HS-PS1-5

A 25.0 mL sample of HCl was titrated to the endpoint with 15.0 mL of 2.0 mol/L NaOH. What is the concentration of HCl?

• 1.6 mol/L

• 0.03 mol/L

• 0.6 mol/L

• 1.2 mol/L