Question

At very low temperatures, the molar heat capacity of rock salt varies with temperature according to Debye's T^3 law: C = kT^3θ^3 where k = 1940 J/(mol⋅K) and θ = 281 K.

A. True
B. False

Answer 1

The assertion about the molar heat capacity of rock salt following the equation C = kT^3θ^3 is false; the actual Debye's T^3 law is expressed differently, with a correct formula being C = 3.33 × 10^4 (T/321K)^3.

Step-by-step explanation:

The statement that at very low temperatures, the molar heat capacity of rock salt varies with temperature according to Debye's T3 law is False. The correct Debye's T3 law is expressed as C = kT3 over the cube of the Debye temperature (T/θ)3 for T much less than θ. The provided equation C = kT3θ3 suggests a direct proportionality of the molar heat capacity to the cube of the Debye temperature, which is incorrect.


Instead, the molar heat capacity of rock salt at low temperatures can be more accurately represented as following the proper Debye T3 law: C = 3.33 × 104 (T/321K)3, where the constant 321 K is the Debye temperature (θ) for the salt.