You need your calculator and paper to write on
Sponsored Links
This presentation is the property of its rightful owner.
1 / 4

You need your calculator and paper to write on PowerPoint PPT Presentation


  • 47 Views
  • Uploaded on
  • Presentation posted in: General

You need your calculator and paper to write on. You will need the chart on page 2 for one of the problems. How many joules of energy is required to change 50mL of liquid water at 85ºC to steam at 115ºC? Some helpful information: ΔH vap (water ) = 40.7 kJ/mol

Download Presentation

You need your calculator and paper to write on

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


You need your calculator and paper to write on

You will need the chart on page 2 for one of the problems.


How many joules of energy is required to change 50mL of liquid water at 85ºC to steam at 115ºC?

Some helpful information:

ΔHvap(water) = 40.7 kJ/mol

ΔHfus(water) = 6.01 kJ/mol

Freezing temperature of water = 0.06ºC

Boiling temperature of water = 99.4ºC

Answer: 117,000

Approx 7 minutes


An 8.50-gram sample of an unknown metal at 118ºC is placed into a coffee-cup calorimeter containing 35.0 mL of water. The water’s temperature increased from 35.000ºC to 36.793ºC. What is the identity of the metal? [You will need to use your packet chart.]

Answer: Brass

Approx 7 minutes


A 3-gram sample of heptane, C7H16, is combusted with 1,050 mL of oxygen gas at STP.

ΔH = - 4819 J/mol rxn.

  • Write the balanced reaction.

  • How much energy will be produced?

  • The energy is used to heat 90 grams of water originally at 17°C. What is the final temperature of the water?

    Answers:

    2) -20.5 J

    3) 17.05°C

    When you finish, get your packet out and work some extra problems!!! No sitting around!

Approx 15 minutes


  • Login