1 / 11

Questions (Clickers)

Questions (Clickers). If you were interested in disrupting the noncovalent interactions between water molecules in ice you could: Shine light on the ice. Stick the ice in a freezer. Hit the ice with a hammer. Add heat to the ice. Questions (Clickers).

halil
Download Presentation

Questions (Clickers)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Questions (Clickers) • If you were interested in disrupting the noncovalent interactions between water molecules in ice you could: • Shine light on the ice. • Stick the ice in a freezer. • Hit the ice with a hammer. • Add heat to the ice.

  2. Questions (Clickers) • When heat is added to liquid propane, (CH3CH2CH3), it warms until reaching the boiling point, and then changes into a gas. Which of the following statements most accurately describes what is going on: • The added kinetic energy is causing the carbon and hydrogen atoms in propane to separate from one another. • The added kinetic energy is causing the disruption of both hydrogen bonds and London dispersion forces between the propane molecules. • The added kinetic energy is causing the disruption of the London dispersion forces between the propane molecules. • The added kinetic energy is causing the propane to change into methane gas.

  3. Questions (Clickers) • When heat is added to liquid ethanol, (CH3CH2OH), it warms until reaching the boiling point, and then changes into a gas. Which of the following statements accurately describes what is going on: • The added kinetic energy is causing the carbon and hydrogen atoms to separate from one another. • The added kinetic energy is causing the disruption of both hydrogen bonds and London dispersion forces between the ethanol molecules. • The added kinetic energy is causing the disruptions of the London dispersion forces between the ethanol molecules. • The added kinetic energy is causing the ethanol to change into methane gas and water vapor.

  4. Questions (Clickers) • Both propane (M = 44 g/mol) and ethanol (M = 46 g/mol) have comparable molecular weights. Which do you predict has the higher boiling point? Explain why. • They should have similar boiling points. • The ethanol should have the higher boiling point. • The propane should have the higher boiling point. • It is hard to tell without doing the experiment.

  5. Questions (Clickers) • When the ice melts from the surface of a pond on a warm spring day, this change is • spontaneous • nonspontaneous

  6. Questions (Clickers) • When the ice forms on the surface of a pond on a cold winter day, this change is • spontaneous • nonspontaneous

  7. Questions (Clickers) • Before going on a picnic on a hot sumer day, you stopby the store and pick up a block of dry ice, CO2(s). • In terms of ΔH alone, is the sublimation of dry ice • Spontaneous • Nonspontaneous

  8. Questions (Clickers) • Before going on a picnic on a hot sumer day, you stopby the store and pick up a block of dry ice, CO2(s). • In terms of ΔS alone, is the sublimation of dry ice • Spontaneous • Nonspontaneous

  9. Questions (Clickers) • Before going on a picnic on a hot sumer day, you stopby the store and pick up a block of dry ice, CO2(s). • At 50°C (This is one hot day!!) the ΔG for the sublimation of dry ice as a • negative value. • positive value.

  10. Questions (Clickers) • You planning to do some surgery on your kitchen table and know that you need to sterilize your instruments by heating them to 120°C. You rummage around in the kitchen cupboards and find a pressure cooker that can heat water to a pressure of 1.4 atm. Will this be sufficient for sterilizing your instruments? (You may use Table 5.6 in your book to answer this question; see the previous slide.) • Yes • No • Explain you answer.

  11. Questions (Clicker) • Pentanoic acid and 1-pentanol have the same number of carbon atoms. Which one is expected to have the higher solubility in water? Explain. • Pentanoic acid • 1 Pentanol • Neither

More Related