Scientific disciplines use a process whereby information is gathered through repeated experiments, evaluation, and review by professional scientists. This information, in the form of laws and theories, is shared with the scientific community through publications. Non-scientific disciplines generally do not use regimented experimentation; instead, they use observation, facts already in existence, and supposition.
A hypothesis is a logical statement that explains an event or answers a question. It is important to scientific thinking because it must be testable — the scientist must be able to support it or disprove it.
Sometimes the results from a one-time experiment are inconclusive — they neither support nor disprove the hypothesis. A new experiment must be conducted or more information collected. Repeatability is the process whereby scientists eliminate bias and test their results by having independent investigators repeat the experiment. If a hypothesis is supported by many experiments and
several different investigators, it is considered reliable.
The scientific method is the process of gathering information and generally involves observation, hypothesis formation, hypothesis testing, critical evaluation of results, and the publishing of findings.
The second law of thermodynamics states that when energy is converted from one form to another, there is a loss of useful energy. This loss is a form of pollution. An example would be the emissions from power plants.
See figure 4.2.
The atoms in a molecule are held together by chemical bonds which result from the interaction of the electrons. During a reaction, electronic attractions are rearranged, and bonds between the atoms are either broken or new ones formed.
The first law of thermodynamics states that energy can be neither created nor destroyed. The second law states that when energy is transformed from one form to another there is a loss of useful energy.
In solids, molecules have a low amount of energy and vibrate close to one another. In liquids, higher-energy molecules are farther apart and flow over each other. In gases, the molecules move rapidly and are far apart.
Five kinds of energy are heat, light, electricity, chemical energy, potential, and kinetic energy.
Different energy forms are of different quality. Electrical energy is of high quality and can be easily transformed to perform a variety of useful actions. Heat in ocean water is of low quality because of the small temperature difference between the ocean in its surroundings. It can do little work for us.
