请问浓硫酸有挥发性吗？浓硫酸的挥发性好不好「专家回答」

浓硫酸有 挥发性吗

是的。浓硫酸具难挥发性、强酸性、强氧化性、 吸水性、脱水性。浓硫酸，俗称坏水，化学分子式为HSO，是一种具有高腐蚀性的强矿物酸。浓硫酸指质量分数大于或等于70%的硫酸溶液。

由于浓硫酸中含有大量未电离的硫酸分子，所以浓硫酸具有吸水性、脱水性和强氧化性等特殊性质。而在稀硫酸中，硫酸分子已经完全电离，所以不具有浓硫酸的特殊化学性质。

发烟硫酸是无色或棕色油状稠厚的发烟液体(棕色是因为其中含有少量铁离子)，具有强烈刺激性臭味，吸水性很强，与水可以任何比例混合，并放出大量稀释热。所以进行稀释浓硫酸的操作时，应将浓硫酸沿容器壁慢慢注入水中，并不断用玻璃棒搅拌。

除了酸固有的化学性质外，浓硫酸还具有自己特殊的性质，与稀硫酸有很大差别，主要原因是浓硫酸溶液中存在大量未电离的硫酸分子(硫酸分子亦可以进行自偶电离)，这些硫酸分子使浓硫酸有很强的性质。

浓硫酸的挥发性好不好

浓硫酸是一种无色透明的液体，也是一种常见的强酸。由于其广泛应用和强腐蚀性，人们往往会对其挥发性产生疑问：浓硫酸的挥发性好不好？

从化学的角度来看，硫酸分子中包含两个氧原子，而氧具有较强的极性和电负性，因此导致硫酸分子之间的分子间力较强。这就意味着浓硫酸的挥发性较差，甚至可以说是几乎不挥发。

但是，实际生活中我们会发现，在室温下开瓶盖时，浓硫酸似乎会“吐露出”一些气体，这是为什么呢？其实，产生这种现象的原因是，由于浓硫酸具有极强的吸水性，所以在室温下，空气中的水分子会被其吸附。随着吸附的水分子增多，会在瓶口形成一层薄薄的液态硫酸蒸汽，这就是所谓的“挥发”现象。

另外，我们常说的硫酸雾其实是由于浓硫酸蒸汽与空气中的水蒸气混合形成的。当浓硫酸暴露在空气中时，由于其吸湿性，会吸附大量的水分子，因此形成的硫酸蒸汽也会带有大量的水分子，形成一种类似于雾的状态。

【英文介绍/For English】：

Yes. Concentrated sulfuric acid is non-volatile, strongly acidic, strong oxidizing, hygroscopic, and dehydrating. Concentrated sulfuric acid, commonly known as bad water, is a highly corrosive strong mineral acid with the chemical formula HSO. Concentrated sulfuric acid refers to a sulfuric acid solution with a mass fraction greater than or equal to 70%.

Because concentrated sulfuric acid contains a large number of unionized sulfuric acid molecules, concentrated sulfuric acid has special properties such as water absorption, dehydration and strong oxidation. In dilute sulfuric acid, the sulfuric acid molecule has been completely ionized, so it does not have the special chemical properties of concentrated sulfuric acid.

Fuming sulfuric acid is a colorless or brown oily thick fuming liquid (brown because it contains a small amount of iron ions), has a strong pungent odor, is highly hygroscopic, can be mixed with water in any proportion, and emits a large amount of dilution heat . Therefore, when diluting concentrated sulfuric acid, the concentrated sulfuric acid should be slowly injected into the water along the wall of the container, and continuously stirred with a glass rod.

In addition to the inherent chemical properties of acid, concentrated sulfuric acid also has its own special properties, which are very different from dilute sulfuric acid. The main reason is that there are a large number of unionized sulfuric acid molecules in the concentrated sulfuric acid solution (sulfuric acid molecules can also undergo self-dual ionization). These sulfuric acid molecules are what give concentrated sulfuric acid its strong properties.