1. Chemistry Review

2. What are subatomic particles?

3. Protons Electrons Neutrons

4. What are their charges ?

5. Protons = + Electrons = - Neutrons = neutral

6. Where are they found ?

7. Protons = nucleus Electrons = shells/ energy levels in the electron cloud (smallest particle) Neutrons = nucleus

8. What is the nuclear model of the atom ?

9. An atom is the smallest unit of an element that upholds all of the properties of that element.

10. What is the mass of an atom and how is that determined ?

11. Everything in the nucleus determines its mass = Protons + Neutrons (no charge)

12. How do atoms define or determine elements ?

13. Protons have a + electrical charge and electrons have a – charge. Atoms that have the same number of + and – do not have an electrical charge.

14. How do protons determine an elements’ identity ?

15. An element can be identified by it’s atomic number = # of protons

16. How do valence electrons determine an element’s chemical reaction ?

17. Electrons are located and arranged on energy levels. 1st shell = 2 / 2 nd shell = 8 3 rd shell = 18 Valence Electrons are on outermost shell – have the highest energy

18. They determine if valence electrons are shared, or stolen, or traded to create new molecules. The reactivity is determined by how easily and readily they react with the valence electrons from other atoms

19. Metals transfer electrons to nonmetals when they react. Nonmetals usually gain or share electrons when they react. Charged atoms are called Ions

20. How are elements arranged on the Periodic Table ?

21. Elements are arranged by increasing order of the atomic #

22. What does the atomic number represent ?

23. Atomic # = number of protons (and usually electrons)

24. What determines the atomic mass of an element ?

25. Number of protons & neutrons Everything in the nucleus Atomic Mass increases when moving to the right and down the periodic table, because of the addition of more atomic particles

26. What do the columns represent ? What do they tell you ?

27. Columns are called Groups of Families All elements in that group have the same # of electrons

28. What do the rows represent ? What do they tell you ?

29. Rows are called Periods Each period tells you how many electron shells the element has.

30. . What physical and chemical properties are determined by investigating the Periodic Table ?

31. Elements in the same Group or Family have similar physical and chemical properties. Earth Metals (1) Highly reactive m Halogens ( 17 )Reactive nonmetal Nobel Gase (18) Least reactive

32.  -------Metals -------> Nonmetals Zigzag/staircase - metalloids

33. What defines a chemical reaction?

34. Atoms of substances rearrange themselves into a new substance. The Reactants combine to form new Products

35. What is a Chemical Equation ?

36. Shows the atomic #’s and molecules making up the reactants and products of a chemical reaction. Subscript = # of atoms ( on right, below line) Coefficient = # of molecules ( on the left, big number)

37. What are the reactants and products of a chemical equation ?

38. Reactants ------  Product ____+____ -----  ________ Anything left of the arrow Anything right of the arrow Arrow means yields or produces

39. What are the four signs that indicate a chemical reaction has taken place ?

40. Produces gas/ bubbles Change in temperature Endothermic-absorbs energy Exothermic-releases energy Precipitate forms (clear liquid to a solid Change in state/color change

41. What are the five kinds of chemical reactions ?

42. Synthesis ___+____---> _______ Decomposition ______-  __+__ Single Replacement __+____--  ______+___ Double Replacement _____+______-  ______+_______