Elements, Compounds, and Mixtures

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include hydrogen (H), oxygen (O), and carbon (C).

Front

What is a compound?

Back

A compound is a substance formed when two or more elements chemically bond together. Examples include water (H2O) and carbon dioxide (CO2).

Front

What is a mixture?

Back

A mixture is a combination of two or more substances that are not chemically bonded. Examples include air, salad, and sand and salt.

Front

What is a solution?

Back

A solution is a homogeneous mixture where one substance (the solute) is dissolved in another (the solvent). Examples include lemonade and saltwater.

Front

What is the most abundant gas in Earth's atmosphere?

Back

Nitrogen (N2) makes up about 78% of Earth's atmosphere.

Front

What is the difference between a homogeneous mixture and a heterogeneous mixture?

Back

A homogeneous mixture has a uniform composition throughout (e.g., saltwater), while a heterogeneous mixture has a non-uniform composition (e.g., salad).

Front

What are some examples of elements?

Back

Examples of elements include gold (Au), silver (Ag), iron (Fe), and helium (He).

Front

What are some examples of compounds?

Back

Examples of compounds include sodium chloride (NaCl), glucose (C6H12O6), and ammonia (NH3).

Front

What is the chemical symbol for copper?

Back

The chemical symbol for copper is Cu.

Front

How many elements are in the periodic table?

Back

As of now, there are 118 confirmed elements in the periodic table.