Calorimetry Lab Analysis (predict specific heat of unknown metal)

In summary, the problem is that the data in the spreadsheet is wrong because the specific heat of water is 4.184 J/gC, which is different from the 50 J/gC that is in the data. The equations that the expert used to calculate the change in temperature were correct, but the equations for calculating the specific heat of the metal were not.
  • #36
Wubblyboofus said:
0.084
Did I input the correct temperatures here?
 
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  • #37
Chestermiller said:
Did I input the correct temperatures here?
yes i think you did
 
  • #38
but i fixed the spreadsheet data and now I am getting 1.1 J/gC
calorimetry is so weird
 
  • #39
Wubblyboofus said:
but i fixed the spreadsheet data and now I am getting 1.1 J/gC
calorimetry is so weird
Let's see your hand calculation.
 
  • #40
4.184*30*76.8/73.3/121.5=1.082
4.184*30*79.3/74/121.5=1.107
4.184*30*75.8/72.8/121.5=1.076

?
 
  • #41
Wubblyboofus said:
4.184*30*76.8/73.3/121.5=1.082
4.184*30*79.3/74/121.5=1.107
4.184*30*75.8/72.8/121.5=1.076

?
is the 76.8 in degrees C or degrees F? Is the 73.3 in degrees C or degrees F? What are the actual initial and final temperatures of cube and water for this case?
 
  • #42
Chestermiller said:
is the 76.8 in degrees C or degrees F? Is the 73.3 in degrees C or degrees F? What are the actual initial and final temperatures of cube and water for this case?
the 76.8 and 73.3 are changes in temperature
 
  • #43
Chestermiller said:
is the 76.8 in degrees C or degrees F? Is the 73.3 in degrees C or degrees F? What are the actual initial and final temperatures of cube and water for this case?
the actual are
trial namemass in gti in Ctf in Cmass water in gti water in Ctf water in Cct in Cct water in Cspecific heat in J/gC
UM1121.599.626.33022.899.673.376.81.082415239
 
  • #44
acronyms
ti initial temperature
tffinal temperature
ggrams
Cdegrees celcius
ctchange in temperature
Jjoules
UMunknown metal trial
LTlead trial
 
  • #45
How can the final temperature of the water be higher than the final temperature of the cube?
 
  • #46
the initial temp of the cube if before i put it into the boiling water
the final temp of the cube is after i put it in the boiling water for a couple minutes
the initial temp of the water is room temp (before i put the boiling cube in)
the final temp of the water is the highest temp the room temp water becomes after putting the cube in
 
  • #47
Wubblyboofus said:
the water ti and tf is how much the room temperature water was heated once the metal (at 212 C) was placed into it. so it goes from about 21 to 26 because the water has high specific heat so it is hard to raise its temperature even if a block of boiling metal is placed into it.
the metal ti and tf however is how much the metal was heated once placed into boiling water. so that would be from 21 to 212.

as i said earlier the procedure went as follows:
put metal into boiling water
metal is now at boiling temperature
put that same metal into room temp water
see how much the room temp water heats
calculate specific heat of metal
use that to identify the metal
You heated the water to 100C not 212C.
 
  • #48
Wubblyboofus said:
the initial temp of the cube if before i put it into the boiling water
the final temp of the cube is after i put it in the boiling water for a couple minutes
Are you aware that this has nothing to do with the measurement you are trying to make? The only reason for putting the cube in the boiling water was to establish its starting temperature for the subsequent measurement.
 
  • #49
tech99 said:
You heated the water to 100C not 212C.
yea i fixed that already
but i can't change the original post for some reason
i changed my spreadsheet though
 
  • #50
Chestermiller said:
Are you aware that this has nothing to do with the measurement you are trying to make? The only reason for putting the cube in the boiling water was to establish its starting temperature for the subsequent measurement.
oh
so would the new one be
water:
21 --> 26
metal:
212 --> 26
 
  • #51
this is due tomorrow dang
 
  • #52
and after i predict this i have to find the percent error of my calculations
 
  • #53
Wubblyboofus said:
oh
so would the new one be
water:
21 --> 26
metal:
212 --> 26
100 —> 26
 
  • #54
Chestermiller said:
100 —> 26
ok let me put it all thru the calculator again ugh
 
  • #55
i really appreciate your guys's help by the way. i probably would have never found my mistakes without you guys
thanks
 
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