Graded Assignment

SCI303B: Chemistry | Unit 1 | Lesson 9: Mid-Unit Test

Name: | Date: |

*Graded Assignment*

**Mid-Unit Test, Part 2**

Answer the questions below. When you have finished, submit this assignment to your teacher by the due date for full credit.

*(10 points)
*

Score |

1. What is Boyle’s law?

· State the definition of the law in words.

· What are the assumptions of Boyle’s law?

· Write at least one mathematical equation that represents the law.

· What can be calculated with Boyle’s law?

· Using a gas-filled balloon as an example, describe what is happening to the gas molecules inside the balloon before and after you squeeze it.

Answer:

*(10 points)
*

Score |

2. You walk in the front door of your home. You smell an onion that someone is cutting in the kitchen. Explain why you are able to smell it, what this process is called, and what other types of substances exhibit this behavior.

Answer:

*(10 points)
*

Score |

3. Draw graphs representing Boyle’s law, Charles’s law, and Gay-Lussac’s law for a fixed amount of gas. Make sure that you label each axis and state the assumptions for each law—that is, the variable(s) that is (are) held constant for each law.

Answer:

Your Score | ___ of 30 |

Graded Assignment

SCI303B/304B: Chemistry | Unit 1 | Lessons 6 and 7: Laboratory: Gas Laws

Name: | Date: |

*Graded Assignment*

**Lab Report**

Answer the questions below. When you have finished, submit this assignment to your teacher by the due date for full credit.

*(10 points)
*

Score |

1. From Part 2 of the lab activity, plot a graph of volume vs. temperature (in kelvins) with the two data points that resulted from your experiment. Draw a straight line connecting the two points, thus assuming a linear relationship between volume and temperature.

The *x*-intercept corresponds to where the volume would be zero and the temperature can be no lower, defined as absolute zero. Absolute zero is 0 K. Compare your results to those expected. How close to absolute zero was your intercept? Why might your value be different from absolute zero?

Answer:

*(10 points)
*

Score |

2. Consider all parts of the experiments that you have just performed.

· What conclusions can you make about the relationship between the volume of a gas and its temperature?

· What conclusions can you make about the relationship between the volume of a gas and its pressure?

· What possible variables have you not accounted for? As you did the procedures, is it possible that the atmospheric pressure may have changed? If it did change over the course of your experiment, then how would your results have been affected?

Answer:

Your Score | ___ of 20 |

Graded Assignment

SCI303B/304B: Chemistry | Unit 2 | Lessons 3 and 4: Laboratory: Factors Affecting Solution Formation

Name: | Date: |

*Graded Assignment*

**Lab Report**

Answer the questions below. When you have finished, submit this assignment to your teacher by the due date for full credit.

*(7 points)
*

Score |

1. Compare and contrast the rate of solution formation between the three physical forms of salt that were placed in the vial and **not** agitated with the three forms of salt that were placed in the vial and **were** agitated.

Answer:

*(7 points)
*

Score |

2. On the basis of your results, what is the relationship between the temperature of the solvent and the rate of solution formation?

Answer:

*(6 points)
*

Score |

3. Use your knowledge of collision theory to explain the results of your experiments in this laboratory.

Answer:

Your Score | ___ of 20 |

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Graded Assignment

SCI303B/304B: Chemistry | Unit 2 | Lesson 10: Unit Test

Name: | Date: |

*Graded Assignment*

**Unit Test, Part 2**

*(5 points)
*

Score |

1. Most fruit juices are a solution of water, sugar, and fruit-specific chemicals. In this solution, identify the solvent and solutes.

Answer:

*(5 points)
*

Score |

2. Explain collision theory and discuss how it can be used to explain why powdered sugar will dissolve in water faster than a cube of sugar.

Answer:

*(5 points)
*

Score |

3. Discuss the difference between molarity and molality, state the units of each, state the symbol for each, and give an example of how each can be used when you are determining the concentration of a solution.

Answer:

*(5 points)
*

Score |

4. Ethylene glycol (C2H6O2) is used as an antifreeze in cars. If 400 g of ethylene glycol is added to 4.00 kg of water, what is the molality? Calculate how much the freezing point of water will be lowered. The freezing-point depression constant for water is *K*f = –1.86°C/*m*. Show your work.

Answer:

Your Score | ___ of 20 |

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