6. Pure vs. mixtures. Homogeneous vs. heterogeneous

Front

What is a pure substance?

Back

A pure substance is a single element or a compound that has a uniform and definite composition.

Front

What is a mixture?

Back

A mixture is a combination of two or more substances that retain their individual properties and can be separated by physical means.

Front

What distinguishes a homogeneous mixture from a heterogeneous mixture?

Back

A homogeneous mixture has a uniform composition throughout, while a heterogeneous mixture has a non-uniform composition with distinct phases.

Front

Give an example of a homogeneous mixture.

Back

An example of a homogeneous mixture is saltwater, where the salt is completely dissolved in water.

Front

Give an example of a heterogeneous mixture.

Back

An example of a heterogeneous mixture is a salad, where the individual ingredients can be seen and separated.

Front

Why is water considered a pure substance?

Back

Water is considered a pure substance because every water molecule (H2O) is identical and it has a consistent composition.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements chemically bond together in a fixed ratio.

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means.

Front

What process is required to separate compounds?

Back

A chemical process is required to separate compounds into their constituent elements.

Front

What is table salt (NaCl) classified as?

Back

Table salt (NaCl) is classified as a compound.