## Chem – Atomic Notation Part 2

What sections should I know before attempting to learn this section?

—> Neutrons

—> Isotopes

—> Ions

How do I use the periodic table to produce element with atomic notation?

In this section YOU WILL HAVE TO USE THE PERIODIC TABLE as a reference. Now that we have tackled the atomic notation part one section lets us try to reverse the question. What if the question gives you the numbers of protons neutrons and electrons and asks for the atomic notation?

STEP 1)  FIRST FOCUS ON THE PROTONS. THE PROTONS WILL TELL YOU WHICH ELEMENT IT IS SO YOU CAN GET THE ELEMENTAL SYMBOL.

STEP 2)  NEXT USE THE PROTONS MINUS THE ELECTRONS TO GET THE CHARGE (top right).

STEP 3)  THEN USE THE PROTONS PLUS THE NEUTRONS TO THE GET MASS.

VIDEO Atomic Notation Demonstrated Example 4: Given the protons, electrons, and neutrons, create the atomic notation for that element. Use this periodic table as a reference.

The element has 36 protons, 36 electrons, and 40 neutrons.

Fill in the protons (in this case 36) in the bottom left corner.

 36

When we look for the proton number on the periodic table 36 protons means the element Krypton (Kr) so we fill in Kr in the center.

 Kr 36

Next we take the protons minus the electrons (36 – 36 = 0) and we get the charge of ZERO. Which means we do not put any notation in the top right corner.

 Kr 36

Then we add the protons and neutrons (36 + 40 = 76) to get the atomic mass of 76. We put that in the top left to complete our answer.

 76 Kr 36

VIDEO Atomic Notation Demonstrated Example 5: Given the protons, electrons, and neutrons, create the atomic notation for that element. Use this periodic table as a reference.

The element has 15 protons, 18 electrons, and 17 neutrons.

Fill in the protons (in this case 15) in the bottom left corner.

 15

When we look for the proton number on the periodic table 15 protons means the element Phosphorus (P) so we fill in P in the center.

 P 15

Next we take the protons minus the electrons (15 – 18 = -3) and we get the charge of -3. Which means we put 3- top right corner.

 P 3- 15

Then we add the protons and neutrons (15 + 17 = 32) to get the atomic mass of 32. We put that in the top left to complete our answer.

 32 P 3- 15

VIDEO Atomic Notation Demonstrated Example 6: Given the protons, electrons, and neutrons, create the atomic notation for that element. Use this periodic table as a reference.

The element has 20 protons, 18 electrons, and 22 neutrons.

Fill in the protons (in this case 20) in the bottom left corner.

 20

When we look for the proton number on the periodic table 36 protons means the element Calcium (Ca) so we fill in Ca in the center.

 Ca 20

Next we take the protons minus the electrons (20 – 18 = 2) and we get the charge of +2. Which means we put 2+ in the top right corner.

 Ca 2+ 20

Then we add the protons and neutrons (20 + 22 = 42) to get the atomic mass of 42. We put that in the top left to complete our answer.

 42 Ca 2+ 20

PRACTICE PROBLEMS: Given the protons, electrons, and neutrons, create the atomic notation for that element. Use this periodic table as a reference.

Ion of the element has 7 Protons, 10 electrons, and 7 neutrons.

 14 N 3- 7

The element has 18 protons, 18 electrons, and 22 neutrons.

 40 Ar 18

Ion of the element has 12 protons, 10 electrons, and 13 neutrons.  