Counting Atoms and Elements

Front

What does it mean if an element symbol has no subscript next to it?

Back

It indicates that there is only 1 atom of this element in the chemical formula.

Front

How many elements are present in the chemical formula NaOH?

Back

There are 3 elements: Sodium (Na), Oxygen (O), and Hydrogen (H).

Front

How many Oxygen atoms are in the molecule H₂O?

Back

There is 1 Oxygen atom.

Front

What is the chemical formula for ethane?

Back

The formula for ethane is C₂H₆.

Front

How many Nitrogen atoms are in the compound (NH₄)₂CrO₄?

Back

There are 2 Nitrogen atoms.

Front

What is a chemical formula?

Back

A chemical formula is a way of expressing the number and type of atoms in a molecule.

Front

What does a subscript in a chemical formula indicate?

Back

A subscript indicates the number of atoms of the element in the molecule.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of one type of atom, while a compound is made of two or more different types of atoms chemically bonded together.

Front

What is the significance of the periodic table in chemistry?

Back

The periodic table organizes elements based on their properties and atomic structure.

Front

How do you determine the number of atoms in a chemical formula?

Back

Count the number of each element's symbol and multiply by the subscript if present.