Found underground and on the sea floor, methane hydrate consists of natural gas molecules trapped within a lattice of frozen water molecules.

甲烷水合物主要存在于地下以及海底，由甲烷分子被锁在固态水晶体格中所组成。

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And so the entropy for this gas here is just - the number of ways of placing the molecule in the lattice.

气体的熵只决定于，分子在晶格中排列的种数。

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In other words if you say, how many vibrations are there in the lattice, well if there are N atoms, each atom in the gas phase would have three degrees of freedom.

换句话说，你会问经各种有多少振动，如果有N个原子，气相中的每个原子有,3个自由度。

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Methane hydrates are frozen water molecules that trap methane gas molecules in a crystalline, lattice-like structure known as a hydrate.

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