1. The study of matter and changes in matter best describes the science of chemistry.
2. Matter that is free to move and fills it's available volume is in the gaseious state. (g)
3. All matter is composed of atoms.
4. The state of matter in which a material has a fefinite volume but no definite shape is the liquid state.
5. The state of matter in which a material has definite shape and definite volume is the solid state.
6. The state of matter in which a material has neither a definite shape nor a definite volume is the gaseous state.
7. the particles in a solid are packed closely together.
8.The state of matter in which a material is most likely to resist compression is the solid state.
9. Under ordinary conditions of temperature and pressure, the particles in a gas are very far from each other.
10. The word equation that represents the reaction that produces water from hydrogren and oxygen is: Hydrogen plus oxygen yields water.
11. Burning ethanol (A type of alcohol) in oxygen produces carbon dioxide and water. The word equation is: ethanol plus oxygen yields carbon dioxide and water.
12. Nitrogen monoxide and oxygen, both colorless gases, form a red-brown gas when mixed.
Nitrogen monoxide and oxygen are called the reactants.
13. A chemical reaction is endothermic if energy is absorbed during the reaction.
14.The following are SI units for density: Kg/m3, g?mL, G/cm3.
15. A change in force of Earth's gravity on an object will effect it's weight.
16.The measure of the quantity of matter is mass.
17. Mass is determined by comparing the mass of an object with a set of standard masses that are a part of a balance.
18. To determine density, the quantities that must be measured are mass and volume.
19. The relationship between the mass M of a material, it's volume V, and it's Density D is DV= M.
20. Density is a physical property.
21. A physical property is a property of matter that can be measured with out changing its chemical nature.
22. Two features that distinguish matter are mass and volume.
23. The melting of candle wax is classified as a physical change because it produces no new substances.
24. Liquid boils at 100 degrees celsius which is a quantitative observation.
25. Salt deposits form from an evaporated liquid is a qualitive observation.
26. Qualitive observations are recorded using nonnumerical information.
27. Quantitative observations are recorded using numerical information.
28. Measurement standards avoid ambiguity.
29. measurement standards must be unchanging.
30. A standard must agree with a previously defined size.
31. Quantity is somthing that has magnitude or size.
32. The choice of unti depends on the quantity being measured.
33. A unit is usually prceded by a number.
example: Measure quantity mass with the unit kilogram.
34. The abreviation that represents a volume unit is mL.
35. Quantity that describes the amountof matter in a given space is density.
36. A unit compares what is being measured with a previously defined size.
37. A Liter is not a base unit.
38. The (SI) Systeme Internationale d'Unites is a metric system that has a standard system of measurement unit: it features seven base units but the five extensively used in chemistry are meter, kilogram, second, kelvin, and mole.
39. The SI base unit for time is second.
40. 1 cubic cenitmeter = 1 mL
41. A physical change is when ice melts. Another example - a glue gun melts a glue stick.
42. A chemical change occers when one or more substances are changed into new sunstances.
43. A chemical change occurs when silver tarnishes, milk sours, wood burns or a leaf changes colors.
44. A useful source of chemical information about the elements is a periodic table.
45. Elements near each other on the periodic table usually have properties similar to each other.
46. Some elements exist as molecules. Some elements exists as atoms.
47. in the same physical state, different molecular forms of the same elements are called allotropes.
48. Oxygen, Phosphorus, sulfur, and carbon exist as allotropes.
49. Ascorbic acid is a pure substance. 5% acetic acid is not a pure substance because water is present as well as acid.
50.. Physical means can be used to separate mixtures.
51. A chemical compound represents the composition of a molecule.
52. Organic substances contain carbon.