### All College Chemistry Resources

## Example Questions

### Example Question #1 : Titrations

The titration of a sample of an solution at an unknown concentration requires of a solution. What is the concentration of the unknown hydrochloric acid solution in ?

**Possible Answers:**

**Correct answer:**

Start by writing the chemical equation for this acid-base reaction.

Next, find the number of moles of that was added.

At the equivalence point of a titration, the moles of acid and the moles of base are the same.

Finally, find the molarity of the solution.

Make sure to round the answer to three significant figures.

### Example Question #2 : Titrations

A sample of sodium hydroxide is titrated with hydrochloric acid. Find the pH of the solution after adding of hydrochloric acid.

**Possible Answers:**

**Correct answer:**

Start by finding the initial number of moles of sodium hydroxide by using the given volume and molarity. Since sodium hydroxide is a strong base, it will dissociate completely into .

Next, find the number of moles of the hydrochloric acid added by using the given volume and molarity. Since hydrochloric acid is a strong acid, all of the will come from the acid.

Now, as the acid is added, it will neutralize some of the base as shown by the following equation:

Since the reactants are found in a ratio, subtract the number of moles of acid added from the number of initial moles of base to get the amount of remaining base.

Now, divide this number of moles by the total volume of the solution to find the concentration of the base.

Next, find the value.

Finally, find the value.

Your answer should have significant figures.

### Example Question #3 : Titrations

Determine the volume in mL of solution it would take to neutralize of a with a solution during a titration.

**Possible Answers:**

**Correct answer:**

Determine the moles of used:

At the equivalence point of the titration:

Convert the moles of to liters:

Convert the liters to milliliters:

### Example Question #4 : Titrations

Determine the volume in mL of solution it would take to neutralize of a with a solution during a titration.

**Possible Answers:**

**Correct answer:**

Determine the moles of used:

At the equivalence point of the titration:

Convert the moles of to liters:

Convert the liters to milliliters:

### Example Question #5 : Titrations

reacts with in aqueous solution according to the chemical equation provided. If it took of a solution to titrate of an solution, what was the concentration of original solution?

**Possible Answers:**

**Correct answer:**

Using the concentration of as a conversion factor, we can convert the volume of to moles by dimensional analysis:

At the equivalence point of the titration:

### Example Question #6 : Titrations

Household vinegar contains the organic compound acetic acid with chemical formula, . Acetic acid reacts with in aqueous solution according to the chemical equation provided. Determine the percentage (by volume) of vinegar in a sample that reacted with of during a titration to reach the equivalence. (Density of =)

**Possible Answers:**

**Correct answer:**

At the equivalence point of the titration:

Convert the moles of to grams:

Using the density of given, convert the grams to mL:

Determine the percentage of by dividing the volume of by the total volume of vinegar:

### Example Question #7 : Titrations

reacts with in aqueous solution according to the chemical equation provided. If it took of a solution to titrate of an solution, what was the concentration of original solution?

**Possible Answers:**

**Correct answer:**

Using the concentration of as a conversion factor, we can convert the volume of to moles by dimensional analysis:

At the equivalence point of the titration:

### Example Question #8 : Titrations

Household vinegar contains the organic compound acetic acid with chemical formula, . Acetic acid reacts with in aqueous solution according to the chemical equation provided. Determine the percentage (by volume) of acetic acid in a sample of vinegar that reacted with of during a titration to reach the equivalence. (Density of =)

**Possible Answers:**

**Correct answer:**

Convert the liters of to moles:

At the equivalence point of the titration:

Convert the moles of to grams:

Using the density of given, convert the grams to mL:

Determine the percentage of by dividing the volume of by the total volume of vinegar: