This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: A substance has a melting point of 20C and a heat of fusion of 3.5 104 J/kg. The boiling point is ... (Read 128 times)

clmills979

  • Hero Member
  • *****
  • Posts: 551
on: Jul 29, 2018
A substance has a melting point of 20C and a heat of fusion of 3.5  104 J/kg. The boiling point is 150C and the heat of vaporization is 7.0  104 J/kg at a pressure of 1.0 atm.
 
  The specific heats for the solid, liquid, and gaseous phases are 600 J/(kgK), 1000 J/(kgK), and 400 J/(kgK), respectively. The quantity of heat given up by 0.50 kg of the substance when it is cooled from 170C to 88C, at a pressure of 1.0 atmosphere, is closest to
  A) 30 kJ. B) 70 kJ. C) 44 kJ. D) 21 kJ. E) 14 kJ.

Question 2

A metal having a work function of 2.8 eV is illuminated with monochromatic light whose photon energy is 3.9 eV.
 
  What is the threshold frequency for photoelectron production? (h = 6.626  10-34 J  s, 1 eV = 1.60  10-19 J)
  A) 6.8  1014 Hz
  B) 2.7  1014 Hz
  C) 7.6  1014 Hz
  D) 8.5  1014 Hz
  E) 9.4  1014 Hz


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

mariahkathleeen

  • Sr. Member
  • ****
  • Posts: 337
Reply #1 on: Jul 29, 2018
Answer to Question 1

B

Answer to Question 2

A


clmills979

  • Member
  • Posts: 551
Reply 2 on: Jul 29, 2018
Thanks for the timely response, appreciate it

momolu

  • Member
  • Posts: 320
Reply 3 on: Yesterday
Excellent

« previous next »
 

Did you know?

Approximately one in four people diagnosed with diabetes will develop foot problems. Of these, about one-third will require lower extremity amputation.

Did you know?

There are actually 60 minerals, 16 vitamins, 12 essential amino acids, and three essential fatty acids that your body needs every day.

Did you know?

Prostaglandins were first isolated from human semen in Sweden in the 1930s. They were so named because the researcher thought that they came from the prostate gland. In fact, prostaglandins exist and are synthesized in almost every cell of the body.

Did you know?

In ancient Rome, many of the richer people in the population had lead-induced gout. The reason for this is unclear. Lead poisoning has also been linked to madness.

Did you know?

Walt Disney helped combat malaria by making an animated film in 1943 called The Winged Scourge. This short film starred the seven dwarfs and taught children that mosquitos transmit malaria, which is a very bad disease. It advocated the killing of mosquitos to stop the disease.

Common trigger point locations, anterior and posterior. Common trigger point locations, anterior and posterior.
Direct thumb pressure to a trigger point. Direct thumb pressure to a trigger point.
Large areas of permafrost are melting Large areas of permafrost are melting
Two-point discrimination Two-point discrimination
Relationship Between the Atlas and the Axis. The Dens of the Axis Provides a Pivotal Point Around Wh Relationship Between the Atlas and the Axis. The Dens of the Axis Provides a Pivotal Point Around Wh
Video: Hyperglycemia Animation

For a complete list of videos, visit our video library