Unknown Substance: c=0.182772277 cal/g*C

Click For Summary

Discussion Overview

The discussion revolves around identifying a substance with a specific heat capacity of 0.182772277 cal/g*C. Participants explore potential candidates for the substance and discuss the implications of precision in specific heat values.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about the identity of a substance with a specific heat of 0.182772277 cal/g*C, explicitly stating it is not glass.
  • Another participant suggests consulting a chart of common substances and their specific heats, mentioning the need for unit conversion if necessary.
  • A participant notes that their table lists glass with a specific heat of 0.18, reinforcing their belief that the unknown substance is not glass.
  • One participant argues that the difference between 0.18 and 0.182772277 is negligible, suggesting that such approximations are often accepted in practice.
  • Another participant emphasizes the importance of including uncertainty in specific heat values and warns against using more digits than the precision of the measurement allows.

Areas of Agreement / Disagreement

Participants express differing views on the significance of precision in specific heat values and whether the unknown substance could be glass. The discussion remains unresolved regarding the identity of the substance.

Contextual Notes

There are unresolved assumptions regarding the accuracy of specific heat values and the implications of precision in measurements. The discussion highlights the variability in reported values for different substances.

PrudensOptimus
Messages
641
Reaction score
0
c = 0.182772277 cal/g * C

What type of substance is it? it's not glass.
 
Science news on Phys.org
Do you have a chart of common substances and their specific heats? If not, I'm sure you could find one on the internet. If the specific heats listed are in different units use the conversion factor 4.184Joules/Calorie.
 
Originally posted by eku_girl83
Do you have a chart of common substances and their specific heats? If not, I'm sure you could find one on the internet. If the specific heats listed are in different units use the conversion factor 4.184Joules/Calorie.


My table only has 0.18 for Glass. And I know is not glass.
 
actually it probably is given the general acceptance of the idea of approximate input giving apporximate output, which is is used as an excuse by lazy textbook writers to give what they consider to be a "significant" number of digits. Basically except for those of us (like me) who are the most anal about precision .18 and .182772277 are the same.
 
A good table of such values will display the uncertianity in the given values. To use digits beyond the given known errors is to introduce garbage in your calculations. If a number is given to 2 or 3 digits, simply assume that the error is .5 of the first unspecified digit.

Any experimentally computed value should include an error analysis of the measurements required to complete the computation.
 

Similar threads

High School Specific heat capacity (the very basics)
  • · Replies 2 ·
Replies
2
Views
2K
Undergrad Extremely strange consequence of the speed of heat value
  • · Replies 19 ·
Replies
19
Views
3K
Undergrad A query about heat capacity and specific heat capacity
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Supercooled water - latent heat of fusion
  • · Replies 17 ·
Replies
17
Views
6K
Undergrad Heat Conductivity with Aluminum Foil
  • · Replies 6 ·
Replies
6
Views
4K
Graduate What is the Specific Heat of an Ideal Blackbody?
  • · Replies 11 ·
Replies
11
Views
8K
Undergrad Heating substances in paper cups?
  • · Replies 4 ·
Replies
4
Views
3K
Problem involving specific heat and graph
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Confusion about the interpretation of specific volume
  • · Replies 18 ·
Replies
18
Views
4K
Undergrad Difference between using temperature in Celsius and Kelvin
  • · Replies 11 ·
Replies
11
Views
4K