Talk:Table of specific heat capacities

Why are the "notable minima and maxima" written in maroon?

Seems like a strange colour to choose. I dont know if i am alone in this, but for me it blended in with the black quite easily. Maybe a bolding, highlight, or other colour would be better. I don't know wikipedia's specific rules on this type of stuff.

Epmtunes (talk) 19:19, 12 May 2020 (UTC)

I agree. It's not bad in the table itself, as it is in bold as well, but in the table there are bold, black numbers which have no stated cause and have no uniting feature (why Lithium at 181 C but not other Lithium?). Furthermore, the maroon data points only appear to be highlighting the highest and lowest values, which can easily be found by sorting by one of the columns. Jeremy Beatson (Use this button to talk to me) 05:39, 17 March 2021 (UTC)

possible wrong values in table?

It seems that the value Cp for Iron is not correct. Multiplying molar mass and molar heat capacity of iron produces different value (0.450) and this value also appears in other sources though I am not able to find a primary source of either of these values. This seems like a good source for the molar heat calacity of iron https://webbook.nist.gov/cgi/cbook.cgi?ID=C7439896&Mask=2&Type=JANAFS&Table=on#JANAFS Ideally the whole table should be verified if this value is not correct and they were taken from the same source...

The page you refer to shows the actual problem, if one plots the actual graph of the specific heat capacity of iron as a function of temperature. The specific heat capacity of iron is far from constant against changing temperature ranges. So, you can only report it for a specific temperature range. Typically tables like ours here lack this detail and the value is given like it is universal. Well, for many elements and materials it is far from it. So, to be taken seriously, any table like the one here should have a temperature range where each specific heat capacity value can be expected to hold. --Jvp2010 (talk) 09:26, 21 September 2023 (UTC)

The heat capacity CV,am for all water seems to be wrong

Substance 	Phase 	Isobaric mass

Water (Steam) - fifth Column: 28.03 = (8,314 * 3.37) = 3.37R (Not 1.12R in last column) Water Liq. 100°C / 0°C - fifth Column: 74.53 = (8,314 * 8.96) = 8.96R (Not 1.12R in last column) Water ice 0°C - value in fifth column should be similiar to value in fourth column (minimal work via expansion) - fourth Column: 38.03 = (8,314 * 4.57) = 4.57R (Not 1.53R in last column) Someone should check my thought and then update the table. — Preceding unsigned comment added by 2003:E4:9702:E501:2DF1:F4DF:55F2:4D99 (talk) 07:53, 17 April 2022 (UTC)

Yes, someone should check this table. It says water at 25°C has the same isobaric mass heat capacity as water 100°C, 4.1813 J/g per degree. For example CRC Handbook giver 4.2159 J/g per degree for 100°C. Maybe add a warning on this page that it is unreliable until someone checks everything? Mletonsa (talk) 12:54, 27 December 2022 (UTC)

In general, the last (seventh) column seems to be wrong for most liquids. Molecular liquids should have heat capacities around 9 R and roughly equal to C_P (since liquids are mostly incompressible). Also, it‘s suspicious that this column is entirely filled while the fifth column is not. 2.244.188.201 (talk) 22:37, 8 May 2023 (UTC)

I would just delete the row where the CP of water at 100 C is stated as 4.18 — Preceding unsigned comment added by 2600:1700:5D0:D490:F9DE:61FC:3261:11C6 (talk) 13:19, 12 July 2023 (UTC)

Awkward non-SI units used in table

The table should use SI-units, f.i. J/kg/K and not J/g/K. Furthermore, as already stated above, several values seem to be wrong.

I'd suggest fully removing the table. This is - in my opinion - much better than confusing readers with a table containing obviously faulty values. 217.111.88.123 (talk) 15:52, 16 August 2023 (UTC)

It seems to be common practice to use both kJ/kg/K and J/g/K for specific heat capacities. I am not sure where this practice originates, but it seems to be widespread. I assume it is due to nice numeric values. However, the unit should be given as

kJ/kg/K to make it SI-compliant. SI-units can have magnitude values in front of them and in this case it is in front of Joules. Jvp2010 (talk) 09:47, 21 September 2023 (UTC)

I think a table would be beneficial in allowing readers to visualize and compare specific heat capacities; I totally agree that we need to correct the faulty values. 2603:7081:333D:DCB3:F465:CC4A:2BA:C88D (talk) 01:12, 16 October 2023 (UTC)

The values for steel are problematic

The table lists some values for "Steel". However, there is no reference to source and no indication about the nature of steel in question. For example, [stainless steel] contains at least 10,5% of [chromium], while [carbon steel] contains only small amount of [carbon]. These additives make a big difference in the heat capacity values. And they vary A LOT (see for example [SAE_steel_grades]). So, any value should have at least a reference to source. Now there is none.

At the same time, it is difficult to find values for steel as the they vary so much. So some values for couple of different basic steels would be most useful. Of course, if one knows the exact composition of the steel in question, the heat capacity could be calculated as mass-average or molar average. But even that may not be correct or even close to correct.

As the provided value for specific heat capacity of steel is very close to the specific heat capacity of iron (that is also very problematic), it can be assumed the value in the table belongs to some low carbon steel, but without reference this is a guess. Jvp2010 (talk) 09:07, 21 September 2023 (UTC)