n.异构体，同分异构体，同核异能素，同质异能素

The two isomers of butane have different chemical properties.
这两种异构体的丁烷具有不同的化学性质。
Isomers can be structural, geometric, or stereoisomers.
异构体可以是结构异构体、几何异构体或立体异构体。
In organic chemistry, cis- and trans-isomers are common types of geometric isomers.
在有机化学中，顺反异构体是几何异构的一种常见形式。
Enantiomers are a type of stereoisomer that cannot be superimposed on their mirror image.
对映异构体是一种不能与其镜像重叠的立体异构体。
Isomers often have similar melting and boiling points, but different reactivity.
异构体通常具有相似的熔点和沸点，但反应性却不同。
The existence of isomers makes it crucial for chemists to identify the specific compound in a mixture.
异构体的存在使得化学家在混合物中识别特定化合物变得至关重要。
Amino acids come in L- and D-isomers, which play a role in protein structure.
氨基酸有L-和D-两种异构体，它们在蛋白质结构中发挥作用。
Isomers can arise from the rotation around a double bond, as seen in butadiene.
通过双键旋转产生的异构体，如丁二烯中可以看到。
Isomers can affect the pharmacological effects of a drug, making them important in medicinal chemistry.
药物的异构体会影响其药理作用，这是医药化学中的重要考虑因素。
Natural products, like cholesterol and vitamin E, often exist as a mixture of isomers.
自然产物，如胆固醇和维生素E，常常以异构体的形式存在。