ISOTOPES POWERPOINT FOR COLLEGE STUDENTS

ISOTOPES POWER POINT FOR COLLEGE STUDENTS

1. THE NATURE OF MATTER Chapter # 02 Topic :ISOTOPES Objective Define nucleon number Define and state isotope of same atoms with different nucleon number

2. ATOMIC STRUCTURE Nucleus Electron Orbit Energy Levels

3. O 16 8 chemical symbol mass number (nucleon number) proton number (atomic number) P=E No. of protons= no. of electrons atomic number (proton n umber) is the number of protons in an atom. Each oxygen atom has 8 protons. As the number of electrons is equal to the number of protons in an atom, each oxygen atom contains 8 electrons. Mass=P+N mass number is the total number of protons and neutrons in an atom . Number of neutrons in the oxygen atom is: 16 – 8 = 8. Interpreting Chemical Symbol

4. Definition of Isotopes Isotopes are atoms of the same element which contains the same number of protons but different number of neutrons . Same P different n

5. Isotopes O 16 8 mass number proton number Oxygen-16 Oxygen-17 Oxygen-18 O O 17 8 18 8 n = 8 n = 17 – 8 = 9 n = 18 – 8 = 10

6. Isotopes Isotopes have the same chemical properties but slightly different physical properties

7. Q. Do all isotopes of the same element have the same mass?

8. Isotopes of Some Elements and Their Atomic Mass

9. Average Atomic Mass The atomic mass of an element is listed below the symbol of each element on the periodic table. Gives the mass of an “average” atom of each element compared to 12 C. Mg 24.31

10. Calculating Average Atomic Mass The calculation for atomic mass requires the percent(%) abundance of each isotope. atomic mass of each isotope of that element. sum of the weighted averages. mass of isotope(1)x (%) + mass of isotope(2) x (%) = Ar 100 100 Ar = (Average atomic mass)

11. Calculating Atomic Mass Mg Isotope Mass Abundance 24 Mg = 23.99 amu x 78.70/100 = 18.88 amu 25 Mg = 24.99 amu x 10.13/100 = 2.531 amu 26 Mg = 25.98 amu x 11.17/100 = 2.902 amu Atomic mass (average mass) Mg = 24.31 amu

12. I know the answer……..

13. RADIO ISOTOPES Parent isotope Radioactive decay heat Daughter isotope

14. Stable vs. Unstable A stable isotope does NOT undergo radioactive (or nuclear) decay . An unstable isotope undergoes radioactive (or nuclear) decay . Unstable isotopes are also known as radioisotopes or radionucleides

15. Uses of Radioactive Isotopes Food irradiation Archaeological dating (carbon-dating) Smoke detectors Radioactive tracers

16. NUCLEON NUMBER electrons

17. Process of emitting energy in the forms of waves or particles.

18. In nucleus there are two types of forces

19. Stable isotopes: They do not naturally decay but exist in natural materials in differing proportions Unstable iso tope Isotopes that continously break down into lower atomic weight isotopes