Elements and Compounds

Front

What is an element?

Back

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

Front

What is a compound?

Back

A compound is a substance formed when two or more elements chemically bond together. Compounds have different properties than the elements that make them up.

Front

Which of the following represents an element: H2O, H2, NaCl, CaCO3?

Back

H2 is the only element among the options.

Front

What is a chemical symbol?

Back

A chemical symbol is a one or two-letter notation used to represent an element, such as H for hydrogen or O for oxygen.

Front

Can a compound be broken down into simpler substances?

Back

Yes, compounds can be broken down into their constituent elements through chemical reactions.

Front

What is the difference between an element and a compound?

Back

An element is a single type of atom, while a compound consists of two or more different types of atoms bonded together.

Front

Give an example of a compound.

Back

Water (H2O) is an example of a compound, made up of hydrogen and oxygen atoms.

Front

What does the formula NaCl represent?

Back

NaCl represents the compound sodium chloride, commonly known as table salt, which is made of sodium and chlorine.

Front

What is the significance of the periodic table?

Back

The periodic table organizes all known elements based on their atomic number and properties, helping to understand their relationships.

Front

What is a molecule?

Back

A molecule is the smallest unit of a compound that retains the chemical properties of that compound, consisting of two or more atoms bonded together.