1. Introduction to Atoms The Fundamental particles of Atoms

2. Match the word in the left to right positive electrical charge particle Atomic number 1 No charge particle 2 Isotope negative electrical charge particle 3 neutron proton number of protons +neutron 4 Atomic mass number of protons in the nucleus 5 Atoms of the same element but different mass number electron 6

3. atom An _____is the smallest particle of an element that has the chemical properties of the element. Copper atoms on silica surface. Distance across = 1.8 nanometer (1.8 x 10-9 m)

4. The Atom Did you know an atom consists of a ….. nucleus electrons Electron cloud Nucleus

6. electronsin space around the nucleus.the number of electrons is equal to the number of protons.

8. mass = 1.672623 x 10-24 g

12. Mass Number, A C atom with 6 protons and 6 neutrons is 12 atomic mass units B atom with 5 protons and 5 neutrons is 10 atomic mass units What is mass number? Mass Number(A)= # protons + # neutrons

13. Atomic number Atomic symbol Atomic Mass(AVERAGE) Nuclear symbol A X Z (or Mass number)

14. Atomic number Atomic symbol Nuclear symbol C atom with 6 protons and 6 neutrons. Write the nuclear symbol of C atom …… Mass number

15. 11B 10B Isotopes Atoms of the same element (same Z) but different mass number (A). Boron-10 (10B) has 5 p and 5 n Boron-11 (11B) has 5 p and 6 n

16. Learning Check – Counting Naturally occurring carbon consists of three isotopes, 12C, 13C, and 14C. State the number of protons, neutrons, and electrons in each of these carbon atoms. 12C 13C 14C 6 6 6 #p+ _______ _______ _______ #no _______ _______ _______ #e- _______ _______ _______ 6 6 6 6 7 8 6 6 6

17. Answers 12C 13C 14C 6 6 6 #p+666 #no678 #e- 6 66

18. Isotopes? Which of the following represent isotopes of the same element? Which element? a). b). c). d). 234 X234 X235 X238 X 92939292

19. Learning Check An atom has 14 protons and 20 neutrons. A. Its atomic number is…. 1) 14 2) 16 3) 34 B. Its mass number is…. 1) 14 2) 16 3) 34 C. Another isotope of this element is… 1) 34X 2) 34X 3) 36X 16 14 14

20. Yes, U R the ultrastudent. Thank you