Final answer:
Graphite and silver are two materials where the specific heat capacity (ℓ) is commonly available but the molar heat capacity (ℓm) may not be, due to complexity of transformation for graphite and the different forms and uses of silver, making the pure molar heat capacity less reported.
Step-by-step explanation:
You are looking for materials where the specific heat capacity at constant pressure (ℓ) might be readily available but the molar heat capacity (ℓm) would not be. The specific heat capacity is a property that tells us how much heat energy is needed to raise the temperature of a given mass of a substance by one degree Celsius. On the other hand, molar heat capacity refers to the amount of heat needed to raise the temperature of one mole of a substance by one degree Celsius.
Typically, for pure elements like graphite (a form of carbon), iron, aluminum, and silver, ℓ is readily available because it is a commonly measured property. However, ℓm may not be as readily available for two main reasons:
- Complexity of transformation
- Difficulty in measurement
So, graphite and silver are two materials for which ℓ might be readily available, while ℓm might not be because of the reasons mentioned above.