7R Chemistry Review

1. All matter is made up of ATOMS.

A A – Electron B B – Neutron C - Proton C 2. Identify each labeled structure in the atom. Describe the charge for each particle. A A – Electron Electrons have a negative charge. B B – Neutron Neutrons have no charge (neutral). C - Proton Protons have a positive charge. C

3.Where are protons and neutrons found in an atom? 4. Where are electrons found in an atom? In the nucleus of an atom. Outside the nucleus of an atom.

5. Which subatomic particle would be found outside the nucleus of an atom? ELECTRON

6. A positively charged particle is a PROTON.

7. Which of the following is not an element? 1. oxygen 3. sodium chloride 2. hydrogen 4. nitrogen

8. A chemical formula like CO2 represents an element 3. an atom    an electron  4. a compound

9. A substance made up of two or more elements that have been chemically combined is a COMPOUND.

10. A substance made up of two or more elements that have been physcially combined is a MIXTURE.

11. A substance that cannot be changed into simpler substances by a chemical change is called a (an) 1. element. 3. liquid. 2. solid. 4. mixture.

12. Element or Compound? a. Carbon (C) b. Carbon dioxide (CO2) c. Water (H2O) d. Nitrogen (N) e. Glucose (C6H12O6) element compound compound element compound

13.

14. Oxygen and hydrogen

15. 6

A 16. Label the following diagrams: Compound, element, mixture D B C

17. Sand and iron particles that are similar in size and color are mixed together in a beaker. What would be the best method of separating the particles? Use tweezers to separate them. Add water to the mixture. Use a magnet to separate them. Pour the mixture into a filter.

18. The substances in a mixture can be separated by physical means because no chemical change occurs when the substances are combined. the physical and chemical properties of the substances change. none of the properties of the substances change. the chemical, but not the physical, properties of the substances change.

19. For the following pictures, identify whether a physical or chemical change is occurring.

Physical

Chemical

Chemical

Physical

Physical

Chemical

20. The chemical composition of the can did not change. It is still made of aluminum.

21. Identify the different phases of matter. Solid, liquid, gas, plasma 22. The particles of a substance are closest together in a _____. solid 23. The particles of a substance that does not have a definite volume or shape is ____. gas

24. Identify the different phases of matter, shown in the diagram below. C liquid solid gas

25. The particles of a substance are closest together in a ____. solid 26. The particles of a substance that does not have a definite volume or shape is ______. gas 27. When a liquid becomes a solid, heat is ____ and the process is called_________. Released, freezing 28. ______ is the process in which liquid changes to gas.  evaporation

29. Matter is anything that has and _________. Mass and volume 30. Identify the following as a physical or chemical change: a. Bending a Paper Clip. physical b. Melting ice into water. c. Baking a cake batter into a cake. chemical d. The rusting of a nail

31. liquid solid

32. 33.

- Atoms are loosely packed Solid - Atoms are tightly packed Gas 34. Identify the solid, liquid and gas! Support your answer. Liquid - Atoms are loosely packed Solid - Atoms are tightly packed Gas - Atoms are very loosely packed

a. Solid to liquid: b. Gas to liquid: c. Liquid to solid: 35. Identify the phase change described. a. Solid to liquid: b. Gas to liquid: c. Liquid to solid: d. Solid to gas: e. Liquid to gas: melting condensation freezing sublimation vaporization

36. For each phase change describe whether energy is RELEASED or ABSORBED. a. Melting: b. Freezing: c. Vaporization: d. Sublimation: e. Condensation: ABSORBED RELEASED ABSORBED ABSORBED RELEASED

37. The particles of a substance are closest together in a solid a liquid a gas plasma

38. The particles of a substance move most readily in a solid a liquid a gas

39. The particles of a substance that does not have a definite volume or shape is a solid 2. a liquid 3. a gas

40. When a liquid becomes a solid, energy does not change is released is absorbed is first absorbed, then released

41. _______ is the process in which liquid changes to gas. 1. Sublimation 3. Condensation 2. Evaporation 4. Combustion

42. The change of a liquid to a solid is called 1. freezing 3. melting 2. sublimation 4. vaporization

43. When substances go directly from the solid phase to the gas phase, the phase change is called 1. sublimation 2. condensation 3. evaporation 4. vaporization

44. What happens to the position of water molecules as they lose heat energy? The slow down and move closer together.

a. Atomic mass: 79.9 b. Mass number: 80 c. # of protons: 35 d. # of electrons: e. # neutrons: 45 f. Atomic #: 45.

a. Atomic mass: 112.41 b. Mass number: 112 c. # of protons: 48 d. # of electrons: e. # neutrons: 64 f. Atomic #: 46.

47. All samples of an element are composed of atoms with the same atomic mass atomic number number of protons and neutrons number of neutrons

48. What is the atomic number for lithium? 3 3 Li Lithium 6.94 1 H Hydrogen 1.01 14 Si Silicon 28.09 18 Ar Argon 39.95 What is the atomic number for lithium? How many protons does an atom of Si have? What is the atomic mass for Argon? How many electrons does an atom of H have? How many neutrons are in an atom of Li? How many electrons are in an atom of Si? How many protons and neutrons are in an atom of Argon? 3 14 39.95 1 4 14 40

49.

50. 51.

52. Explain how the periodic table of elements is arranged. They are arranged according to atomic number. 53. Elements at the left of the periodic table are known as ______. metals 54. Elements at the right of the periodic table are known as _______. nonmetals

55. Explain some of the properties of metals. They are malleable, ductile, have luster, and are good conductors of heat and electricity 56. Explain some of the properties of nonmetals. They are brittle, have no luster and they are not good conductors of heat and electricity.

57. a. b. Cd, Cu Br, P c. Group 18

58.

In W Fe O a. I am a member of the Boron family with 49 protons. 59. Use a periodic table to help you identify each element. Give its symbol for the answer. a. I am a member of the Boron family with 49 protons. b. I have a total of 74 electrons in an atom. c. I have an atomic mass of 55.847. d. I have 8 neutrons in an atom. In W Fe O

They have the same (BUT NOT IDENTICAL) properties. 60. The elements oxygen, sulfur, selenium and tellurium are all found in the same group (16) on the table. What do we know about the elements in that family? They have the same (BUT NOT IDENTICAL) properties.

61. a. In what family is neon found? b. What do we call those elements in that group? Family 18 Noble gases

Which element is a metalloid? 1. S (Sulfur) 3. Si (Silicon) 62. Which element is a metalloid? 1. S (Sulfur) 3. Si (Silicon) 2. Ba (Barium) 4. Br (Bromine)

63. Explain what occurs to the atomic number when moving from left to right on the periodic table. Atomic number increases.

Mg A B C P D E F K G H I A B C D E F G H I Fill in the correct number for each letter using the information provided. 64. Element Atomic Number Atomic Mass # of Protons # of Neutrons # of Electrons Mg 12 24 A B C P 15 D E 16 F K G 39 H I 19 A B C D E F G H I

The answers are … Element Atomic # Atomic Mass Protons Neutrons Electrons Mg 12 24 A B C P 15 D E 16 F K G 39 H I 19 12 12 12 31 15 15 19 19 20

65. Which three elements have the most similar chemical properties? Ar, Kr, Br K, Rb, Cs B, C, N O, N, Si

66. Which element is a noble gas? hydrogen oxygen neon nitrogen

80. Explain the difference between an acid and a base. An acid has an excess of H+ ions and a base has an excess of OH- ions. 81. Identify 2 examples of acids. Hydrochloric acid, lemon juice 82. Identify 2 examples of bases. Soap, drain cleaner 83. What does the pH scale measure? The strength of an acid or base.

67. What does it mean when a substance is neutral? It is not an acid or a base. 68. What pH would neutral substance have? 7 69. Which numbers on the pH scale represent an acid? Any number below 7.

70. Classify each of the following as acidic, neutral, or basic pH = 2.3 pH = 6.5 pH = 8.5 pH = 11.7 pH = 13.4 pH = 7.0 acidic acidic basic basic basic neutral