Molar entropy converter
Convert molar entropy and molar heat capacity between J/(mol·K), the old entropy units, and multiples of the gas constant R.
That's 1.33× as high as liquid water, while an organic solvent is 1.2× higher. That is about 12.03 times the gas constant R.
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The same units serve molar entropy and molar heat capacity, because the two have identical dimensions.
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Three things worth knowing
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1 cal/(mol·K) = 4.184 J/(mol·K)
And R itself is 8.314 J/(mol·K), or 1.987 cal/(mol·K), which is why the number 1.987 turns up throughout older physical chemistry.
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Why R keeps appearing
Every ideal-gas heat capacity is a simple multiple of R: 3R/2 for a monatomic gas, 5R/2 for a diatomic one at room temperature. Counting in R makes the pattern visible.
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Molar is not specific
J/(mol·K) is per mole; J/(kg·K) is per kilogram. Converting between them needs the molar mass, so they are not interchangeable units of the same thing.
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Background
About molar entropy
Entropy and heat capacity per mole are both measured in J/(mol·K). Older tables use calories per mole per kelvin, once called the entropy unit, and theory papers often quote multiples of R, the gas constant, because that is where the numbers come from.
A monatomic ideal gas has a heat capacity of exactly 3R/2, or 12.47 J/(mol·K), whatever the gas.