Practice Counting Atoms

Front

What is the coefficient in a chemical formula?

Back

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

Front

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

Back

To determine the number of atoms in a compound, multiply the coefficient by the subscript of each element in the formula.

Front

What is a subscript in a chemical formula?

Back

A subscript is a small number written to the right of an element symbol that indicates the number of atoms of that element in a molecule.

Front

In the compound 4(2NaAlO2), how many Aluminum (Al) atoms are there?

Back

There are 4 Aluminum (Al) atoms.

Front

In the compound 3(H2O), how many Oxygen (O) atoms are there?

Back

There are 3 Oxygen (O) atoms.

Front

What is the total number of atoms in the compound 3(CO2)?

Back

The total number of atoms is 9.

Front

In the compound 4(H2O), how many Hydrogen (H) atoms are there?

Back

There are 8 Hydrogen (H) atoms.

Front

In the compound 5(NH3), how many Hydrogen (H) atoms are there?

Back

There are 15 Hydrogen (H) atoms.

Front

What is the formula to calculate the total number of atoms in a compound?

Back

Total atoms = Coefficient × (Sum of all subscripts in the formula).

Front

What does the term 'molecule' refer to in chemistry?

Back

A molecule is a group of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound.