Science benchmark

1. proton charge and location – positive (+) and in the nucleus of atom

2. neutron charge and location – neutral (o) and in the nucleus of atom

3. electron charge and location – negative (-) and outside nucleus in electron cloud

4. atomic number def and determines – number of protons of atom and determines the element it is

5. nucleus location, charge, made of – center of atom, positive charge, and made of protons and neutrons

6. valence electrons purpose and location – determines properties of atom and outermost level of electrons

7. (boxes below)  

8. common property of all p. table elements – all are pure substance, each element has same type of atoms

9. most metallic elements (metal like properties) - Group 1 & 2; left side of p. table, good conductors & shiny

10. least metallic elements - Group 17 & 18 nonmetals; right side to the p. table, poor conductors & dull

11. Group 1 name and properties – alkali metals; most reactive metals and 1 valence electron

12. Zig zag line purpose – location of metalloids between metals and nonmetals

13. Group 2 name & properties – alkali-earth metals; little less reactive than group 1, & 2 valence e-

14. Group 3-12 name, element type, and location – Transition metals and middle of p. table

15. Group 17 name and properties – halogens, most reactive nonmetals, 7 valence electrons  

16. Group 18 name and properties – noble gases, least reactive of elements, full valence electron level

17. group number purpose – tells number of valence electrons atoms have in the column, not transition metals 

18. exception to group number rule – helium, a noble gas in group 18, only has 2 valence electrons

19. chemical change of reactants?–bonds of reactants break, reform for NEW products with different properties

20. signs of chemical change - color change, heat/light/sound/gas bubbles produced, bubble/foam produced

21. law of conservation of mass/matter – mass/matter cannot be created nor destroyed; only changes forms

22. atoms in a chemical reaction must – # of reactants atoms = # products atoms; everything must be same

23. ionic compound formed by – metal and nonmetal; valence electrons are transferred, example NaCl, neutral

24. cation charge and formed by – positive ion made by metals; always lose valence electrons

25. anion charge and formed by – negative ion made by nonmetals; always gain valence electrons

26. Group 1 cation charge – alkali metals always make +1 charge examples H⁺¹, K⁺¹ 

27. Group 2 cation charge – alkali-earth metals always make +2 charge examples Ca⁺², Mg⁺² 

28. Group 13 cation charge – metals always make +3 charge example Al⁺³ 

29. Group 15 anion charge – nonmetals always make -3 charge (gain 3 valence electrons)  N^-3 

30. Group 16 anion charge – nonmetals always make -2 charge (gain 2 valence electrons)  O^-2, Se^-2 

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31. Group 17 anion charge – halogen nonmetals always make -1 charge (gain 1 val. e-) ex Cl^-1, Br^-1 

32. ionic compound/ charge – metal/ nonmetal = cation/anion cancel = neutral;  Al⁺³Cl^-1Cl^-1Cl^-1 = Al₁Cl₃ 

33. covalent compound formed by – nonmetal and nonmetal; share valence electrons; example CO₂,neutral

34. writing compound formula – Li₂O₁ = 2 means 2 Li atoms and 1 means 1 O atom

34. prefixes list – 1 mono, 2 di, 3 tri, 4 tetra, 5 penta, 6 hexa, 7 hepta, 8 octa, 9 nona, 10 deca

35. suffix of compound name rule – goes on last element name in compound; example dioxide

36. compound name rules – capitalize first element and lowercase all that follow; prefix at front 

              of element name  and Li₂O₁ use numbers to determine prefix; example Dilithium monoxide 

37. ionic properties – good conductor, high melt point, highly solubility (dissolve easily), brittle, neutral

38. covalent properties – poor conductor, low melt point, low solubility (doesn’t dissolve easily), neutral

39. balancing equations – coefficient and subscript are multiplied for each element;

40.  Label equation 2Ca + O₂  -->  2CaO  -       Reactants      (yields)       Products

2Ca + O₂    →    2CaO

(subscript) Little 2 is # of atoms         big 2 is # of molecules (coefficients)

41. Is H₂O   +  CO₂     →    H₂ CO₃   balanced?                          Yes,   H₂O   +  CO₂     →    H₂ CO₃ 

Same number of atoms in reactants and products for each type:  2 H   1 C    3 O   →     2 H   1 C   3 O  

42.         -     Pure substance since one thing, also an element because all same atom

43.          -  Pure substance since one thing, all are the same molecule/compound

44.    What does each circle & line represent? -  Each circle/dot is an atom, stick is the bond

45. physical changes are - state change, change in size and shape, example melting ice, weathering

46.  chemical changes result in  -  new substances being produced

47.  physical changes result in   -  no new substance produced

48. compounds have what charge?  -  Compounds are neutral, charges (if have them) cancel out

49. elements in a group have common what? - all have common properties since same valence electrons