Apologia Chemistry Module 11 Test Review

2.

The substance being dissolved is the...

Solution
Solute
Solvent
Percipitate

Correct Answer

A. Solute

Explanation

The solvent (usually water) is the substance dissolving the solute. The solution is the solute and the solvent together. The percipitate is a substance that doesn't dissolve.

Rate this question:

3.

If we increase the temperature of a solution and more solute dissolves, then the solute is a solid.

True
False

Correct Answer

A. True

Explanation

Think about sugar in tea

Rate this question:

1

4.

If the solubility of a solute isn't affected by temperature, the solute is a...

Solid
Liquid
Gas

Correct Answer

A. Liquid

Explanation

If the solubility of a solute isn't affected by temperature, it means that the solute remains equally soluble at different temperatures. Liquids are generally more soluble than solids or gases because their particles are already in a dispersed state, making it easier for them to mix with the solvent. Therefore, if the solute is not affected by temperature, it is likely to be a liquid.

Rate this question:

5.

Exothermic reactions become...

Cold.
Hot.
Pressurized.

Correct Answer

A. Hot.

Explanation

Exo means out. Therm means heat. Endothermic reactions become cold.

Rate this question:

6.

How many moles of HCN are used during the reaction if 0.768 moles of KCN are produced?

One-half as many
The same amount
Twice as many

Correct Answer

A. The same amount

Explanation

Make a proportion with the moles over the balancing numbers. Then solve for the moles of HCN.

Rate this question:

7.

The reason that the hot Dr. Pepper exploded with more force after we shook it up is because...

The solubility of gases decrease with increasing temperature.
The solubility of gases increase with increasing temperature.

Correct Answer

A. The solubility of gases decrease with increasing temperature.

Explanation

The hot Dr. Pepper couldn't dissolve as much gas as the cold one. That's why it spewed when we shook then opened it.

Rate this question:

8.

Write this equation down. We'll use the same equation in several questions. We want to make 50 grams of KCN. How many moles is this?

1.30 moles
0.768 moles
5.28 moles

Correct Answer

A. 0.768 moles

Explanation

Got grams? Want moles? Divide by the AMU.

Rate this question:

9.

If used 0.768 moles of HCN and made it from a 1.51 M solution of HCN, how many liters did I use?

0.509 Liters
4.31 Liters
0.287 Liters

Correct Answer

A. 0.509 Liters

Explanation

Remember that molarity is Moles/Liters so moles/Molarity = Liters

Rate this question:

10.

Change to ml: 0.509 Liters

0.000509 ml
50.9 ml
509 ml

Correct Answer

A. 509 ml

Explanation

To change liters to milliliters, multiply by one thousand. Here is the original question: How many ml of a 1.51 M solution of HCN would be required to make 50.0 grams of potassium cyanide? Know these steps from these questions!

Rate this question:

11.

When 7.5 grams of NaCl are added to 100.0 grams of water, what is the change in the water's freezing point? molality of water = 1.86

9.52 degrees C
4.76 degrees C
-4.76 degrees C
-9.52 degrees C

Correct Answer

A. -4.76 degrees C

Explanation

Delta T =( - 2) (1.86)((7.5 grams/58.5 moles)/0.1 kg of water))

i = 2 for NaCl because it breaks into 1 Na ion and 1 Cl ion.
Remember to change the 100 grams of water into Kg by dividing by 1000.

Rate this question:

12.

To find the molality if you have grams of solute and g of solvent...

Correct Answer

A.

Explanation

grams/AMU gets moles. grams/1000 gets kg. Molality is moles/kg.

Rate this question:

13.

Delta T = i K m is the formula for freezing point depression.

True
False

Correct Answer

A. False

Explanation

This is the formula for boiling point elevation. The freezing point depression formula has a negative in front of the i.

Rate this question:

14.

If the delta T from the last question is -4.76, what is the water's new freezing point?

27.24
0
-4.76
95.24

Correct Answer

A. -4.76

Explanation

Since water freezes at 0 degrees C, 0-4.76=-4.76.
Be careful! Delta T is not always the final temperature only when you're using water and calculating freezing point.

Rate this question:

15.

Check all that are true.

To find molality, you need to know how many moles you have.
To find molality, you need to know the mLs of the solute.
To find molality, you need to know the weight of the solvent.
Molality is used to find the boiling point elevation.
Molality is used to find the freezing point depression.
Molality is used to find the ions in a solute.
Molality is a concentration unit.

Correct Answer(s)

A. To find molality, you need to know how many moles you have.
A. To find molality, you need to know the weight of the solvent.
A. Molality is used to find the boiling point elevation.
A. Molality is used to find the freezing point depression.
A. Molality is a concentration unit.

Explanation

The correct answer is: To find molality, you need to know how many moles you have.,To find molality, you need to know the weight of the solvent.,Molality is used to find the boiling point elevation.,Molality is used to find the freezing point depression.,Molality is a concentration unit.

Molality is a concentration unit that is defined as the number of moles of solute per kilogram of solvent. Therefore, to find molality, you need to know how many moles of solute you have and the weight of the solvent. Molality is used to calculate the boiling point elevation and freezing point depression, which are colligative properties of a solution. Additionally, molality is a concentration unit that expresses the amount of solute in a given amount of solvent.

Rate this question:

16.

Put these in order of ability to raise a liquid's boiling point from least to greatest.

They would all raise the boiling point the same.

Correct Answer

A.

Explanation

NH3 is a covalent molecule so it doesn't break into ions. It's i is 1. NaCl's i is 2, and K2CO3's i is 3.

Rate this question:

Apologia Chemistry Module 11 Test Review

The solubility of a solute depends on...

Quiz Preview

The substance being dissolved is the...

If we increase the temperature of a solution and more solute dissolves, then the solute is a solid.

If the solubility of a solute isn't affected by temperature, the solute is a...

Exothermic reactions become...

How many moles of HCN are used during the reaction if 0.768 moles of KCN are produced?

The reason that the hot Dr. Pepper exploded with more force after we shook it up is because...

Write this equation down. We'll use the same equation in several questions. We want to make 50 grams of KCN. How many moles is this?

If used 0.768 moles of HCN and made it from a 1.51 M solution of HCN, how many liters did I use?

Change to ml: 0.509 Liters

When 7.5 grams of NaCl are added to 100.0 grams of water, what is the change in the water's freezing point? molality of water = 1.86

To find the molality if you have grams of solute and g of solvent...

Delta T = i K m is the formula for freezing point depression.

If the delta T from the last question is -4.76, what is the water's new freezing point?

Check all that are true.

Put these in order of ability to raise a liquid's boiling point from least to greatest.