Molecular Weights and Atomic Structure

The video tutorial explains how to calculate the molecular weight of the nitrate ion (NO3 minus). It begins by identifying the atomic weights of nitrogen and oxygen from the periodic table. Nitrogen has an atomic weight of 14.01 g/mol, and oxygen has an atomic weight of 16.00 g/mol. Since there are three oxygen atoms in NO3, the weight of oxygen is multiplied by three. The total molecular weight is calculated by adding the weight of nitrogen to the total weight of oxygen, resulting in a molecular weight of 62.0 g/mol for NO3 minus.

What is the atomic weight of nitrogen as found on the periodic table?

• 12.01 g/mol

• 14.01 g/mol

• 16.00 g/mol

• 18.02 g/mol

How many oxygen atoms are present in the NO3- ion?

• Four

• Three

• Two

• One

What is the atomic weight of a single oxygen atom?

• 14.01 g/mol

• 15.99 g/mol

• 17.00 g/mol

• 16.00 g/mol

What is the total weight of the three oxygen atoms in NO3-?

• 32.00 g/mol

• 48.00 g/mol

• 60.00 g/mol

• 50.00 g/mol

What is the molecular weight of the NO3- ion?

• 64.0 g/mol

• 58.0 g/mol

• 60.0 g/mol

• 62.0 g/mol