1. Ch. 4/5 Notes Day 3
1/28/16

2. Objectives
SWBAT explain how protons, neutrons, and electrons function together in an atom.
SWBAT calculate numbers of neutrons, protons, and electrons in an element, given atomic number, and atomic mass.

3. This is what we use today…n p+ e-
Particle
Symbol
Relative Charge
Relative Mass (proton=1)
Actual Mass (g)
Electron e- 1-
1 1836
9.11 x 10-28
In the Nucleus…
Proton p+ 1+ 1
1.674 x 10-24
Neutron n
1.675 x 10-24

4. All of this information is in the Periodic Table
Element Name
Atomic Number – the number of protons that are in the nucleus of one atom of an element. **Also equal to the number of electrons in the element. Remember, they have to be neutral!!
Chemical
Symbol
Atomic Mass – the SUM of the number of protons and neutrons that are in the nucleus of one atom of an element.

5. Let’s Practice… Element Name Chemical Symbol # of Protons Element Name
# of Electrons
# of Neutrons
Element Name
Chemical Symbol
# of Protons
# of Electrons
# of Neutrons

6. Ch. 4/5 Notes Day 4
2/1/16

7. Objectives
SWBAT calculate numbers of neutrons, protons, and electrons in an element, given atomic number, and atomic mass.
SWBAT determine whether or not a given “unknown element” is an isotope of another

8. Isotope
An element that has the SAME number of protons (atomic #) but DIFFERENT number of neutrons.
Elements with the SAME number of protons are the SAME element.
**The atomic Mass on the periodic table is the most common mass of that element. You could think of it as the “average weight” of an element.

9. Example All Oxygen atoms have 8 protons, but can have different numbers of neutrons
16.999
17.999

10. Because scientists are ridiculous…
Here is another important way to write atomic number and atomic mass B 11
Atomic Number 5
Atomic Mass

12. Which of the following “unknown” elements are isotopes of Platinum
194 78
194 77
196 78

13. Which of the following “unknown” elements are isotopes of Tin
120 50
116 50
117 51

14. Which of the following “unknown” elements are isotopes of Antimony
120 50
121 50
123 51