| A | B |
|---|
| Chemistry | the study of the composition of matter, the stuff things are made of and the changes that matter undergoes |
| organic chemistry | the study of essentially all subtances containing carbon |
| inorganic chemistry | the study of subtances that do not contain carbon |
| analytical chemistry | concerned with the composition of substances |
| physcial chemistry | is concerned with theories and experiments that describe the behavior of chemicals. |
| biochemistry | is the study of the chemistry of living things. |
| plastics | also called polymers, are gigantic molecules with a high strength-to-weight ratio. |
| photosynthesis | when the energy of the sun is used to build the chemicals for life. |
| Human Genome Project | scientists are working on identifying and determining the molecular structures of all human genes. |
| Global warming | the unnatural heating of the Earth's surface due to an increase in the Greenhouse Effect. |
| ozone layer | a layer of O3 gas particles that surrounds the upper layer of the atmosphere and protects the earth from incoming solar radiation. |
| scientific method | a method of inquiry involving observation, experiments, hypotheses, and broad explanations called theories. |
| observation | using yours senses to obtain information directly. |
| hypothesis | a proposed explanation or reason for what is observed. |
| theory | a broad and extensively tested explanation of why experiments give certain results.It is widely accepted The Big Bang theory.. |
| scientific law | a concise statement that summarizes the results of many observations and experiments. A scientific law describes a natural phenomenon without attempting to explain it.No matter how many times you test it the results are always the same.--Law of Gravity |
| Gay-Lussac's law | summarizes what happens when a sealed, gas-filled container is heated. |
| experiment | a means to test a hypothesis. |
| Steps of scientific methods | 1st observation, 2nd scientific question, 3rd hypothesis, 4th experiment (test it ) 5th collect and analyze data, 6th draw conclusion, 6th repeat experiment |
| physical change | an alteration of a subtance that does not change the subatance. You still have the same subtance that you started with |
| examples of physical changes | change in color, texture, shape, size, state/phase, temperature, and density |
| chemical change | after you have altered a subtance that subtance is now a different subtance than it was before you altered it. |
| examples of chemical changes | gives of heat, absorbs heat, gives of light, burns, color, density, texture, and color |
| density | the ratio of the mass of an object to its volume |
