Unit 2 Test Study Guide: Atomic Structure and the Periodic Table

Transcription

1 Unit 2 Test Study Guide: Atomic Structure and the Periodic Table 1. What is an atom? Give the definition. An atom is the building block of all matter. It is the basic particle from which all elements are made. 2. Define molecule, and give 3 examples of molecules. A molecule is the combination of two or atoms held together through a chemical bond. Examples include O2, H2O, and MgSO4 3. There are 3 subatomic particles in the atom. Fill in the blanks in the following chart, including the name, charge, and location of the particle. Particle Charge Location Neutron Neutral It is located in the nucleus. Electron Negative It is located in the orbitals or the electron cloud. Proton Positive It is located in the nucleus. 4. Label the atom below: 1. neutron 4. nucleus 2. electron 3. proton

2 Zn I Br How do you know how many protons an atom of a certain element will have? What number should you look for? The number of protons is the same as the atomic number of the element because the number of protons defines the element. 9. When drawing the Bohr Models of atoms, each electron orbital can hold a MAXIMUM number of electrons. Fill in the missing numbers from the following chart. Energy Shell Maximum Number of Electrons 1st 2 2 nd 8 3 rd 18 Bohr Model Practice Draw a Bohr model for the following elements. Indicate the number of protons and number of neutrons in the nucleus, and the number of electrons in each energy shell of the atom. 10. Magnesium 11. Phosphorus

3 S8P1f PERIODIC TABLE 12. Where are metals located on the periodic table? The metals are located on the left of metalloids on the periodic table in periods two through seven and groups one through twelve, including periods two through seven in group thirteen, periods five through seven in group fourteen, period six and seven in group fifteen, and period seven in group sixteen. 13. List 3 properties of metals. Metals are conductors, malleable, and shiny. 14. Give 5 examples of metallic elements. Silver, Strontium, and Potassium are examples of metallic elements. 15. Where are nonmetals located on the periodic table? Nonmetals are located to the right of the metalloid on the periodic table. Specifically, nonmetals are in groups seventeen, eighteen, and in period two of groups fourteen, fifteen, and sixteen, in period three of groups fifteen and sixteen, and in period four of group fourteen. 16. List 3 properties of nonmetals. Nonmetals are ductile, brittle, and dull. 17. Give 5 examples of nonmetals. Five examples of nonmetals include Selenium, Chlorine, Helium, Hydrogen, and Carbon. 18. Where are metalloids located on the periodic table? Give 3 examples of metalloids. Metalloids are located along the staircase starting at period two, group thirteen. 19. How is the periodic table arranged? Write a paragraph and use the following words: Atomic number, group, period, stairstep line The periodic table is arranged into groups and periods based upon the atomic number of each element. The atomic numbers increase across each period and then by column. The increasing order reads like a book. Each group and period reflects different characteristics of the elements. The elements that have similar characteristics will be in the same group. The elements that are in the same period will have the same number of valence electrons, which reveals their ability to bond with other elements. In addition, the elements are also divided into metals and nonmetals, which are to the left and right of the stairstep line, respectively. The stairstep line marks where the metalloids are located.

4 20. What is a valence electron? Valence electrons are the electrons found on the outer-most electron orbital of an atom s electron cloud. 21. Fill in the chart below. Given the group number, identify the name of that group/family, the number of valence electrons that elements in that group have, and an example of an element in that family. Group # Group name # of valence example electrons in group 1 Alkali Metals 1 Potassium 2 Alkaline Earth Metals 2 Beryllium 3-12 Transition Metals varies Gold 17 Halogens 7 Fluorine 18 Noble Gasses 8 Helium 22. Which elements do NOT typically react with other elements? Noble gases 23. What are the most reactive metals? What are the most reactive nonmetals? Alkali metals are the most reactive metal. Halogens are the most reactive nonmetals. The periodic table is arrange into: 24. Horizontal rows, called periods. 25. Vertical columns, called groups/family. C 26. Elements with similar chemical properties are in the same on the periodic table. a. period c. group b. row d. ion

5 The following blank periodic table has a few elements labeled with the letters A-F. Use what you know about the periodic table to answer the questions below. A B E C D F 27. a halogen? C 28. a noble gas? D 29. a metalloid? E 30. an element that would not react with other elements? D 31. the letter with the highest atomic number? F 32. the letter with the least atomic mass? A 33. the metals that are the most reactive A, B F is also a transition metal. Use the clues to identify the elements described below: 34. Alkaline earth metal 35. Transition metal 60 neutrons 38 electrons 10 th group Strontium Palladium 36. Halogen, period Alkali metal, 48 neutrons Fluorine Caesium

6 38. What is an ion? An ion is an atom that has a positive or negative charge because it has gained or lost at least one electron. 39. What is the difference between ionic and covalent bonding? Be specific. An ionic bond is the chemical bond between two atoms in which the electrons of one atom is transferred to another, creating ions because the charge of the atoms change. Ions are bonded through their opposite charges. A covalent bond is the bond between two atoms in which they share one or more valence electrons in their cloud. 40. Give an example of an ionic and a covalent bond. An example of an ionic bond is Chlorine and Sodium (any metal and nonmetal). An example of a covalent bond is Chlorine and Oxygen (any nonmetal and nonmetal).

7 S8P1b MATTER 41. Define matter Anything that has mass or takes up space 42. Complete the concept map below. Pure Substance Matter Mixture Element Compound Heterogeneous Homogenous 43. Label the following substances as being: A. Element B. Compound C. Heterogeneous mixture D. Homogeneous mixture A 1. Gold (Au) D 5. Salt water B 9. Water (H2O) B 2. Sugar (C12H22O11) B 6. Salt (NaCl) A 10. Silver (Ag) D 3. Air C 7. Salad A 11. Fluorine (F) C 4. Pizza B 8. Limestone (CaCO3) D 12. Steel (It is an alloy, so it is a mixture) 44. For each of the statements below determine if it describes an element (E), compound (C), or mixture (M). C 2 elements chemically joined together M can be separated by physical means M substances physically combined C substances lost their properties when combined E pure substance that consists of only 1 type of atom 45. What is the difference between a pure substance and a mixture? _C/E cannot be separated by physical means C all have a molecular/chemical formula A pure substance is an element or a compound. It can be bonded or separated through a chemical reaction. The parts of a compound may or may not keep its properties when combined. A mixture can be classified as homogenous or heterogeneous mixture. It can be combined or separated through a physical change. The parts of a mixture will keep its properties when combined.

8 46. Label the following as: a) pure substance (element) b) pure substance (compound) c) mixture of elements d) mixture of compounds B C D D A C S8P1g MATTER 47. What does the Law of Conservation of Mass state? The Law of Conservation of Mass states that matter cannot be created or destroyed; therefore, the mass of the reactants must equal the mass of the products. 48. What is the difference between the product and the reactant? The reactants are the components of a chemical equation that you begin with and the product is the result of the combination of the reactants through a chemical reaction. 49. Juanita mixes 2 grams of substance X with 3 grams of substance Y in a flask. After the substances react, gas does not escape. She records the mass of the new substance. What mass does she record? 2 grams of X + 3 grams of Y = 5 grams of the new substance. The Law of Conservation of Mass demonstrates this. 50. For the chemical reactions shown below, list the elements on both sides of the equation, and tell how many atoms of each element there are. Then indicate if the reaction is balanced or unbalanced. a. 4Al + 3O2 2Al2O3 b. Al + 6HCl AlCl3 + 3H2 Aluminum 4 atoms Oxygen (3*2=6 atoms) Aluminum: (2*2) 4 atoms Oxygen: (2*3) 6 atoms Balanced Aluminum: 1 atom Hydrogen (6*1) 6 atoms Chlorine (6*1) 6 atoms Aluminum 1 atom Chlorine 3 atoms Hydrogen: (3*2=6 atoms) Unbalanced

9 c. Na2CO3 + HCl 2NaCl + H2O + CO2 d. 2P + 5Cl2 2PCl5 Sodium (Na): 2 atoms Phosphorus (2*1) =2 atoms Carbon 1 atom Chlorine (5*2) =10 atoms Oxygen 3 atoms Hydrogen 1 atom Phosphorus (2*1) =2 atoms Chlorine1 atom Chlorine (2*5) =10 atoms Sodium (Na): 2 atoms Balanced Carbon 1 atom Oxygen (2 +1)= 3 atoms Hydrogen 2 atoms Chlorine2 atoms Unbalanced e. 6 CO2 + 6 H2O C6H12O6 + 6 O2 Carbon: 6 atoms Oxygen: (2*6) + 6 = 18 atoms Hydrogen: (2*6) = 12 atoms Carbon: 6 atoms Hydrogen: 12 atoms Oxygen: (6 + (6*2)) = 18 atoms Balanced f. NH4OH + KAl(SO4)2*12H2O Al(OH)3 + 2 (NH4)2SO4 + KOH + H2O Nitrogen: 1 atom NH4: 1 Hydrogen: (12*2)= 29 atoms SO4: 2 Potassium:1 atom OH: 1 Aluminum 1 K: 1 Oxygen: 1 + (4*2) +1 =10 atoms Al:1 Sodium: (4*2)= 8 atoms OR H2O:12 Nitrogen: (2*2)= 4 atoms NH4: (2*2) =4 atoms Hydrogen: 2 + (2*2)+ 1 +2= 9 atoms SO4: 2 atoms Potassium:1atom OH:3+1 = 4 atoms Aluminum 1 atom K: 1 atom Oxygen: =8 atoms Al: 1 atom Sodium:1 atom H2O 1 atom unbalanced ***See if you can balance the unbalanced equations***