Elements, Compounds and Mixtures

Front

What is the definition of an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means and is made up of only one type of atom.

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 distinguishes a mixture from a compound?

Back

A mixture is a combination of two or more substances that retain their individual properties and can be separated by physical means, while a compound has a fixed composition and properties.

Front

What is an example of a pure substance?

Back

A pure substance is a material that has a constant composition and consistent properties throughout, such as distilled water or helium gas.

Front

What is the chemical formula for water?

Back

The chemical formula for water is H2O.

Front

What happens when electricity is passed through water?

Back

When electricity is passed through water, it undergoes electrolysis, producing hydrogen and oxygen gases.

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 is the significance of the periodic table in chemistry?

Back

The periodic table organizes all known elements based on their atomic number, electron configuration, and recurring chemical properties.

Front

What is an example of a chemical reaction that produces a compound?

Back

An example is the reaction between hydrogen and oxygen to form water (2H2 + O2 -> 2H2O).

Front

What is the role of chemical bonds in the formation of compounds?

Back

Chemical bonds, such as ionic or covalent bonds, hold the atoms of a compound together, determining its properties.