溶液是由至少两种物质组成的均一、稳定的混合物，被分散的物质（溶质）以分子或更小的质点分散于另一物质（溶剂）中。 水可以作为溶剂用来溶解很多种物质，用水作溶剂的溶液，即称为水溶液。

There are two main types colloids and suspensions.
有两种主要类型:胶体和悬浮液·
Today we're going to talk about mixtures
今天,我们将讨论混合物,
specifically mixtures with water.
特别是与水相关的混合物·
A mixture is a physical not a chemical combination of two or more substances.
混合物是两种或多种物质的物理(而非化学)结合·
Each substance in a mixture keeps its individual characteristics.
混合物中的每种物质保持其独特的特性·
A solution also called a homogeneous mixture
溶液,也叫做均匀混合物,
consists of very tiny particles mixed so uniformly that the mixture has the same properties throughout.
包含非常微小的颗粒,它们均匀地混合在一起,使得整个混合物具有相同的性质·
In contrast a heterogeneous mixture consists of significantly larger particles that are not uniformly distributed and are more easily seen.
相比之下,异质混合物包含较大的颗粒,这些颗粒分布不均匀,更容易被看到·
The components of a heterogeneous mixture can usually be separated easily.
异质混合物的组成成分通常可以轻松分离·
Homogeneous water based mixtures are called aqueous solutions.
均匀的水基混合物叫做水溶液·
The dissolved substance is called the solute
溶解的物质叫做溶质,
and the substance that dissolves the solute in this case water is called the solvent.
溶解溶质的物质(在本例中是水)叫做溶剂·
Water is sometimes referred to as the universal solvent because it can dissolve more substances than any other liquid.
水有时被称为"万能溶剂",因为它可以溶解比任何其他液体更多的物质·
Water can dissolve many substances because of the polar nature of water molecules.
水能够溶解许多物质,因为水分子具有极性·
This allows water molecules to surround and hold on to other small polar molecules.
这使得水分子能够包围并吸附其他小的极性分子·
As a result the polar molecules spread out evenly throughout the water.
因此,极性分子均匀地分布在水中·
Remember water is the solvent.
记住,水是溶剂·
Water's polar nature also allows the slightly positive and slightly negative charges on its molecules to dissolve ionic compounds known as salts.
水的极性特性还使得水分子上的微弱正电荷和微弱负电荷能够溶解离子化合物,称为盐·
Water does this by separating the compound into negatively and positively charged particles called ions.
水通过将化合物分解成带负电和带正电的粒子,称为离子,从而实现溶解·
The negative poles of water molecules surround the positive ion from the compound
水分子的负极包围化合物中的正离子,
and the positive poles of water molecules surround the negative ion from the compound.
水分子的正极包围化合物中的负离子·
Solutes and solutions are so small and uniformly distributed that solutions are always transparent.
溶质和溶液非常小且均匀分布,因此溶液总是透明的·
You can see right through them.
你可以透过它们看到·
Now let's talk about heterogeneous aqueous mixtures.
现在,让我们谈谈异质水溶液·
Colloids and suspensions differ primarily in the size of their particles within the water.
胶体和悬浮液的主要区别在于它们在水中粒子的大小·
In colloids the particles mixed in the water are larger than the water molecules
在胶体中,混合在水中的颗粒大于水分子,
but are still too small to see with the naked eye.
但仍然太小,肉眼看不见·
As big as these particles are they're still small enough that the random motion of the water molecules keep them mixed within the water.
这些颗粒虽然很大,但它们仍然足够小,水分子的随机运动使得它们保持在水中混合·
In contrast suspensions contain even larger particles than those in colloids
相比之下,悬浮液中含有比胶体中更大的颗粒,
but the particles are just small enough to be suspended in water when stirred or shaken.
但这些颗粒足够小,可以在搅拌或摇动时悬浮在水中·
Over time however the particles in a suspension start to settle to the bottom of the container.
然而,随着时间的推移,悬浮液中的颗粒会开始沉淀到容器底部·
Heterogeneous water mixtures such as colloids and suspensions are never transparent.
异质水混合物,如胶体和悬浮液,永远不透明·
They're always cloudy hazy or opaque and you can't see through them.
它们总是浑浊的、模糊的或不透明的,无法透过它们看·
In this example the colloid is milk and the suspension is sand in water.
在这个例子中,胶体是牛奶,悬浮液是水中的沙子·
To recap mixtures are physical rather than chemical combinations of two or more substances
总结一下,混合物是两种或多种物质的物理而非化学结合,
and each substance in the mixture keeps its individual characteristics.
且混合物中的每种物质保持其个体特性·
A mixture may be a solution which is a homogeneous mixture consisting of very tiny particles mixed so uniformly that the mixture has the same properties throughout
混合物可以是溶液,它是一个均匀的混合物,包含非常微小的颗粒,它们均匀地混合在一起,使得整个混合物具有相同的性质;
or a mixture may be heterogeneous with larger particles that are not uniformly distributed and are more easily seen.
或者混合物是异质的,包含更大的颗粒,这些颗粒分布不均匀,更容易被看到·
Aqueous solutions are homogeneous water based mixtures consisting of tiny ions or molecules dissolved in water.
水溶液是均匀的水基混合物,包含溶解在水中的微小离子或分子·
A solute is the dissolved substance in a solution.
溶质是溶液中溶解的物质·
A solvent is the substance that dissolves the solute.
溶剂是溶解溶质的物质·
Water is called the universal solvent because it dissolves more substances than any other liquid.
水被称为万能溶剂,因为它能溶解比任何其他液体更多的物质·
Aqueous colloids and suspensions are heterogeneous mixtures consisting of larger particles that are less uniformly distributed and more easily separated than the particles in aqueous solutions.
水溶胶体和悬浮液是异质混合物,包含较大的颗粒,这些颗粒分布不均匀,比水溶液中的颗粒更容易分离·
内容操作
视频
教程课件
单词卡片