Qualitative Chemistry Unit 3 Review Assignment ANSWERS. Completion: Write the word or phrase that best completes each sentence in the blank.

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1 Qualitative Chemistry Unit 3 Review Assignment ANSWERS Completion: Write the word or phrase that best completes each sentence in the blank. 1. A compound has _2 or more capital letters in its formula, while an element has 1 capital letter in its symbol. 2. According to Dalton s Atomic Theory, all elements are composed of atoms. 3. According to Dalton s Atomic Theory, all atoms of the same element are identical. 4. According to Dalton s Atomic Theory, when atoms combine to form compounds, they do so in _small whole number ratios. 5. A molecule of C6H5OH contains _6 atoms of carbon, 1 atoms of oxygen, and _6 atoms of hydrogen. 6. A molecule of Ni(MnO4)3 contains _1_ nickel atoms, _3 manganese atoms, and 12_ oxygen atoms. 7. The identity of an element is determined by its atomic number_, which is the number of protons in its nucleus. 8. _Metals usually form cations. 9. Nonmetals usually form anions. 10. Cations contain more_ protons than electrons, and anions contain fewer protons than electrons. 11. When strontium combines with chloride to form a compound, the formula for the compound is SrCl The neutrons provide stability for an atom s nucleus and are responsible for isotopes. 13. The electron is the smallest atomic particle, while the neutron is the largest. 14. The proton is the atomic particle with a charge of The neutron is the atomic particle with no charge. 16. The electron is the atomic particle with a charge of -1.

2 17. The properties of an atom are determined by _the number and arrangement of the electrons in its electron cloud. 18. The isotope Cd contains _48_ protons, _48_ electrons, and _64_ neutrons. 19. The symbol for an isotope that has contains 6 protons, 8 neutrons, and 6 electrons is 14 6C. 20. The nucleus of an atom is composed of protons and neutrons. 21. The Periodic Table is arranged by increasing atomic number. 22. The rows in the Periodic Table are called periods. 23. The columns in the Periodic Table are called _groups or families. 24. The metals and nonmetals are separated by the stairstep on the Periodic Table. 25. Elements that have properties of both metals and nonmetals are called metalloids. 26. There are 7 diatomic elements, and 11_elements that are gases at room temperature. 27. Bromine and mercury are the only elements that are liquid at room temperature. 28. The elements in Group 2 are known as the _alkaline earth metals_. 29. The elements in Group 17 are known as the _halogens. 30. The elements in Group 1 are known as the alkali metals. 31. The elements in Groups 3-12 are known as the _transition metals. 32. The elements in Group 18 are known as the noble(inert) gases. 33. The elements that are usually listed below the Periodic Table are called the inner transition metals. 34. JJ Thomson is credited with discovering the electron. His model of the atom was called the plum pudding model. 35. Rutherford_ is credited with discovering the nucleus. His model of the atom was called the _nuclear model. 36. Chadwick is credited with discovering the neutron. 37. Bohr is known for the planetary model of the atom, and is credited with quantized energy levels.

3 38. _Schrodinger_ is credited with coming up with the current model of the atom. 39. Democritus and Dalton thought the atom was a small indivisible, homogeneous sphere. 40. An ion has a charge of 2+ and has 27 electrons. The symbol for this ion is _Cu 2+ _. Short Answer: Answer the following questions. 41. Describe the current model of the atom. Be sure to include a labeled drawing as part of your answer. Look at your cheat sheet for the Schrodinger model 42. One of my favorite sayings in chemistry is, It s all about the electrons! Explain why this could be considered true. Think about what the function of the electron is. 43. How many protons, neutrons and electrons would be found in an atom of Pd- 107? Explain how you arrived at your answer (including calculations would be a great idea.) There are 46 protons, 47 electrons and 61 neutrons. You need to be able to do the work. 44. How did Dalton s Atomic Theory explain the Law of Constant Composition? As part of your answer, explain the Law of Constant Composition. Look at your notetaker. 45. Calculate the number of protons, electrons, and charge for the following ions. Give the name and symbol. Show all your work. a. Silver loses 1 electron #protons = atomic # =47 Atom: #electrons = # protons = 47 Ion: # electrons = # electrons in atom - # electrons lost = 47-1 = 46 Charge = # protons # electrons = =+ 1 Symbol: Ag +1 Name: silver ion b. Lead loses 4 electrons #protons = atomic # =82 Atom: #electrons = # protons = 82 Ion: # electrons = # electrons in atom - # electrons lost = 82-4 = 78 Charge = # protons # electrons = =+ 4 Symbol: Pb 4+ Name: lead(iv) ion

4 c. Nitrogen gains 3 electrons #protons = atomic # =7 Atom: #electrons = # protons = 7 Ion: # electrons = # electrons in atom + # electrons gained = 7+3 = 10 Charge = # protons # electrons = 7-10 =-3 Symbol: N 3- Name: nitride ion d. Astatine gains 1 electron #protons = atomic # 85 Atom: #electrons = # protons =85 Ion: # electrons = # electrons in atom + # electrons gained = 85+1 = 86 Charge = # protons # electrons = =-1 Symbol: At 1- Name: astatide ion e. Calcium becomes anion Symbol Ca 2+ # protons = atomic # = 20 # electrons = # protons charge = 20 2 = 18 Name: calcium ion f. Phosphorus becomes an ion Symbol P 3- # protons = atomic # = 15 # electrons = # protons charge =15 (-3) = 18 Name: phosphide ion 46. Write the formulas for the compound formed from the following. Show your work a. Cs and Te Cs +1 Te -2 Cs2Te b. Ca and O Ca +2 O 2- Ca2O2 CaO c. Mn 4+ and SO4 2- Mn 4+ SO4 2- Mn2(SO4)4 Mn(SO4)2

5 d. Ni 3+ and Cl Ni 3+ Cl 1- NiCl3 e. Mg and C2H Mg 2+ C2H3O2 1- Mg(C2H3O2)2