Key Idea.
Section 1
Pure Substances
A pure substance is made of only one type of particle (atom or molecule) throughout. Whether you look at a spoonful or a bucketful, the composition is uniform.
This consistency means a pure substance has a fixed set of properties. Water is always H₂O, and Iron is always Fe.
Section 2
Mixtures vs. Substances
Most things in the world are mixtures, combinations of two or more substances that are physically blended but not chemically bonded. Soil, air, and saltwater are mixtures.
In a mixture, the individual substances keep their own properties. However, in the Westfield case, the rust is not a mixture of iron and dirt; it behaves as a single, new substance with its own unique properties.
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Section 1
Pure Substances
A pure substance is made of only one type of particle (atom or molecule) throughout. Whether you look at a spoonful or a bucketful, the composition is uniform.
This consistency means a pure substance has a fixed set of properties. Water is always H₂O, and Iron is always Fe.
Section 2
Mixtures vs. Substances
Most things in the world are mixtures, combinations of two or more substances that are physically blended but not chemically bonded. Soil, air, and saltwater are mixtures.
In a mixture, the individual substances keep their own properties. However, in the Westfield case, the rust is not a mixture of iron and dirt; it behaves as a single, new substance with its own unique properties.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter