1. Week 2

2. Meter Metric unit of length

3. Liter Metric unit of volume

4. Gram Metric unit of mass

5. Volume The amount of space an object occupies

6. Mass Amount of matter in an object

7. Hypothesis Reasonable guess that can be tested and is based on what is known and what is observed.

8. Scientific Theory A possible explanation for repeatedly observed patterns in nature supported by observations and results from many investigations.

9. Variable Any factor that can affect the results of an experiment

10. Independent variable In an experiment, the variable that is manipulated or controlled by the experimenter.

11. Dependent Variable In an experiment, the variable that responds to changes in the independent variable; the variable being measured.

12. Week 3

13. 1) matter Anything that has mass and takes up space.

14. 2) Law of conservation of matter States that matter is not created or destroyed but only changes its form

15. 3) density Physical property of matter that can be found by dividing the matter’s mass by its volume

16. 4) Chemical property Characteristic of something that permits its change to something new

17. 5) Physical property Any characteristic of matter – such as color, shape, and taste – that can be detected by the senses without changing the identity of the matter

18. 6) gas Matter that does not have a definite shape or volume; has particles that move at high speeds in all directions

19. 7) solid A substance with a definite shape and volume

20. 8) liquid A substance that has a definite volume but no definite shape

21. 9) Chemical change Any change of a material into a new material with different properties

22. 10) Physical change Any change in the size, shape, form, or state of matter in which the matter’s identity remains the same

23. Week 4

24. 1) Precision A description of how close measurements are to each other

25. 2) Accuracy Compares a measurement to the true value

26. 3) Meniscus The curve seen at the top of a liquid in response to its container

27. 4) Observation an act or instance of noticing or perceiving; regarding attentively or watching; the habit of observing or noticing.

28. 5) Mass Measure of the amount of matter making up an object

29. 6) Weight A measure of the pull of gravity on the mass of an object

30. 7) Density Physical property that compares the mass of a substance per unit volume

31. 8) Balance Tool used for measuring mass

32. 9) Volume The amount of space matter occupies

33. 10) Graduated Cylinder Tool used to measure volume

35. Week 5

36. 1) atom The basic building block of all matter that is the smallest unit of an element that still has the chemical properties of that element.

37. 2) molecule Smallest unit of a compound; formed when atoms join

38. 3) States of matter Also called phases of matter; solid, liquid, gas, and plasma

39. 4) Solid Have a fixed shape and a fixed volume.

40. 5) Liquid Have no fixed shape, they take the shape of their container, but they do have a fixed volume.

41. 6) Gas No fixed shape or volume, gases take the shape of their container and completely fill it.

42. 7) Physical properties A characteristic of a substance that can be observed directly or measured with a tool without changing the composition of the substance. Examples include: volume, mass, weight, density, texture, and color

43. 8) Physical change Any change in a substance in which the composition of the substance does not change. Examples include: stretching a rubber band, smashing a pumpkin, melting ice, and slicing a carrot.

44. 9) Pure substance a kind of matter that cannot be separated into other kinds of matter by any physical or chemical process

45. 10) Compound A pure substance composed of more than one type of element chemically combined in a fixed proportion

46. Yeah!

47. 1) Uniform without variations in detail; constant; unvarying; undeviating

48. 2) reactivity the ability of an atom, molecule, or compound to undergo a chemical reaction with another atom, molecule, or compound.chemical reaction

49. 3) combustibility capable of catching fire and burning; flammable

50. 4) viscosity the property of a fluid that resists the force tending to cause the fluid to flow.force

51. 5) pH the symbol used to express how acidic or basic a solution is on a scale of 0 to 14, where less than 7 represents acidic, 7 neutral, and more than 7 basic.

52. 6) precipitate to separate a substance in solid form from a solution

53. 7) solution a homogeneous, molecular mixture of two or more substances.mixture

54. 8) Phase change The relationship between temperatures and changes of state

55. 9) heat The transfer of thermal energy between two objects at different temperatures.

56. 10) temperature Measure of the average kinetic energy of the particles in a sample of matter.

57. Week 7

58. 1) miscible capable of being mixed

59. 2) immiscible not miscible; incapable of being mixedmiscible

60. 3) condensation The process by which a gas changes to a liquid

61. 4) vaporization The process by which a liquid changes into a gas

62. 5) Melting point The temperature at which a solid changes into a liquid; is the same temperature as freezing point

63. 6) Freezing point The temperature at which a liquid turns into a solid; that same temperature as melting point

64. 7) sublimation A phase change from solid directly to gas or from gas directly to a solid, without ever turning into a liquid

65. 8) Boiling point The temperature at which a liquid changes to a gas

66. 9) Convection current Movement of a gas, liquid, or plastic solid caused by variations in density that result from uneven heating of matter

67. 10) evaporate To change from a liquid to a gas at or below the boiling point

68. Week 8

69. 1) electron Subatomic particle that carries a negative charge

70. 2) Electron cloud Area of space around the nucleus of an atom where electrons are found

71. 3) atom The smallest part of an element that keeps all the properties of that element

72. 4) Energy level The different areas for an electron in an atom

73. 5) Chemical bond The force that holds two atoms together

74. 6) protons Subatomic particles found in the nucleus of an atom that have a positive charge

75. 7) neutrons Subatomic particles found in the nucleus of an atom that have no charge

76. 8) ion An atom that is no longer neutral because it has gained or lost an electron

77. 9) molecule The neutral particle formed when atoms share electrons

78. 10) compound A pure substance containing two or more elements that are chemically bonded

79. Week 9

80. 1) element Natural or synthetic material that cannot be broken down into simpler materials by ordinary means; has unique properties and is generally classified as metal, metalloid, or nonmetal.

81. 2) Valance electrons Electrons located in the outermost energy level of an atom

82. 3) Atomic number The number of protons in the nucleus of an atom

83. 4) Atomic mass Also known as atomic weight; the average mass of an atom of an element

84. 5) Periodic table of elements A chart that organizes information about all of the known elements according to their properties

85. 6) Valance number the number of electrons needed to fill the outermost shell of an atomelectronsatom

86. 7) Subatomic particle a particle smaller than an atom

87. 8) Democritus A Greek philosopher who proposed the idea of an atom; a particle so small that it could not be divided

88. 9) John Dalton A British chemist and school teacher; showed through experimentation and observation in the 1700’s that – All substances are made of atoms. Atoms of the same element are exactly alike and atoms of different elements are different Atoms join with other atoms to make new substance.

89. 10) J. J. Thomson British scientist; in 1897 discovered that there are small particles inside the atom.