Protons Protons

Protons

• Protons

• +1 Charge
• 1 amu (atomic mass unit)
• 1amu=1.7 * 10-24 g

• Neutrons

• 0 (neutral) charge
• 1amu

• Electrons

• -1 Charge
• Found around the nucleus in an electron cloud
• Virtually no mass

In a typical atom you will have the same number of protons and electrons, what charge does this give the atom?

• In a typical atom you will have the same number of protons and electrons, what charge does this give the atom?

• 0 Charge, or it is neutral!

No

• No

• If it did you would have a NEW element…more on this later!

Yes!

• Yes!

• This is called an Ion

• If the atom is missing an electron it will be a Positive Ion.
• If the atom gains and electron it will be a Negative Ion.

Yes!

• Yes!

• This is called an isotope, it will cause the MASS of the atom to change

Each element’s properties can be determined by the information in its “box” as well as its placement on the Table

• Each element’s properties can be determined by the information in its “box” as well as its placement on the Table

• See pages 768/69 to review the information!

Element Symbol

• Element Symbol

• Zr is Zirconium

• Atomic Number- tells the number of protons in one atom of the element

• Zr has 40 Protons
• (therefore it also has 40 electrons)

• Atomic Mass (Mass Number)

• Tells number of protons and neutrons combined (40 + ? = 91)

My atomic number is 51, my name is…

• My atomic number is 51, my name is…

• Antimony

• My atomic mass is 39.95, my name is…

• Argon

• My atomic mass is 183.85, my name is…

• Tungsten

• My atomic number is 102, my name is…

• Nobelium

My name is Sulfur and I have this many protons

• My name is Sulfur and I have this many protons

• 16

• My atomic number is 19, this is my name and how many electrons I have

• Potassium, 19 electrons

• My name is Cadmium, I have this many protons and neutrons combined

• 112

Each element has a unique atomic number

• Each element has a unique atomic number

• The number of protons for an element’s atom is constant and unique

• The number of electrons will equal the number of protons UNLESS the atom is an ion

Element D has 6 protons and 7 neutrons

• Element D has 6 protons and 7 neutrons

• Element F has 7 protons and 7 neutrons

• Different Element

• Element J has 27 protons and 32 neutrons

• Element L has 27 protons and 33 neutrons

• Isotope

• Element T has an atomic number of 20 and an atomic mass of 40.

• Element Z has an atomic number of 20 and an atomic mass of 41.

• Isotope

Look at the periodic table and find Carbon

• Look at the periodic table and find Carbon

• What is the atomic number?

• What is the mass number?

• “Carbon 12” is the most common form of Carbon

• But you’ve heard of Carbon 14…That is an isotope of Carbon – it has two more neutrons, adding 2 amu to its mass…but it still has only 6 protons

• To name an Isotope

• Element Name – Mass #

Gravitational Force

• Gravitational Force

• Attractive force between all objects in the universe
• Gravity depends upon mass of and distance between objects…
• This force is not very strong in the atom

• Electromagnetic Force

• Opposites attract; likes repel
• Protons & electrons
• Electrons and Nucleus

Strong Force (the physicists got original naming this one)

• Strong Force (the physicists got original naming this one)

• Holds protons and neutrons together to make the nucleus
• Greater than electromagnetic force between protons (since the protons would repel each other)

• Weak Force – Yes, it’s a very weak force

• Deals more with radioactive decay and nuclear fusion

Columns are called groups or families, and as family members, they have similar properties

• Columns are called groups or families, and as family members, they have similar properties

• Rows are called periods. They do not share properties, but properties change as one goes from left to right

Using the periodic table, draw what you think a model of an atom of oxygen would look like

• Using the periodic table, draw what you think a model of an atom of oxygen would look like

• You should have 8 protons and 8 neutrons in the nucleus, and 8 electrons surrounding the nucleus.

Find the atomic number of Hydrogen and add to it the atomic number of Beryllium;

• Find the atomic number of Hydrogen and add to it the atomic number of Beryllium;

• Multiply Lithium’s atomic number by the answer in step 1;

• Add five and divide by the atomic mass of Helium;

• Add four to the answer in step 3;

• The result is the atomic number of this element…

• Fluorine

Multiply the protons of Lithium by the neutrons of Boron;

• Multiply the protons of Lithium by the neutrons of Boron;

• Add the electrons of Carbon;

• Divide by the atomic number of Magnesium;

• Add the protons of Arsenic;

• Divide by the mass number of Lithium

• The result is the atomic number of this element…

• Boron, Atomic number

Multiply the atomic number of Beryllium by the number of protons in Neon;

• Multiply the atomic number of Beryllium by the number of protons in Neon;

• Subtract the atomic number of Carbon;

• Add the number electrons of Helium;

• Divide by the number of protons in Fluorine;

• Subtract the number of electrons in Lithium;

• The result is the atomic number of this element…

• Hydrogen