Counting Atoms

Front

What is a coefficient in a chemical formula?

Back

A coefficient is a number placed in front of a chemical formula that indicates how many molecules or atoms of that substance are present.

Front

In the compound C2H8O, how do you calculate the total number of atoms?

Back

Add the subscripts: 2 (C) + 8 (H) + 1 (O) = 11 total atoms.

Front

How many different elements are present in the compound C6H12O6?

Back

There are 3 different elements: Carbon (C), Hydrogen (H), and Oxygen (O).

Front

What is the total number of atoms in the compound 2B1F3?

Back

The total number of atoms is 2 (B) + 1 (B) + 3 (F) = 6 atoms.

Front

How do you identify the number of atoms in a compound?

Back

Count the total of all the atoms represented by the subscripts in the chemical formula.

Front

What does the subscript in a chemical formula represent?

Back

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

Front

If a chemical formula has no subscript, what does that mean?

Back

It means there is one atom of that element in the molecule.

Front

In the formula H2O, how many hydrogen atoms are there?

Back

There are 2 hydrogen atoms.

Front

What is the total number of atoms in the compound C3H6?

Back

There are 3 (C) + 6 (H) = 9 total atoms.

Front

How many total atoms are in the compound C4H10?

Back

There are 4 (C) + 10 (H) = 14 total atoms.