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Physical Sciences Standards and Benchmarks
Physical Sciences Standard 8:
Understands the structure and properties of matter
Level III (Grade 6-8)
- Knows that matter is made up of tiny particles called atoms, and different arrangements of atoms into groups compose all substances
- Knows that atoms often combine to form a molecule (or crystal), the smallest particle of a substance that retains its properties
- Knows that states of matter depend on molecular arrangement and motion (e.g., molecules in solids are packed tightly together and their movement is restricted to vibrations; molecules in liquids are loosely packed and move easily past each other; molecules in gases are quite far apart and move about freely)
- Knows that substances containing only one kind of atom are elements and do not break down by normal laboratory reactions (e.g., heating, exposure to electric current, reaction with acids); over 100 different elements exist
- Knows that many elements can be grouped according to similar properties (e.g., highly reactive metals, less-reactive metals, highly reactive nonmetals, almost completely nonreactive gases)
- Knows that substances react chemically in characteristic ways with other substances to form new substances (compounds) with different characteristic properties
- Knows factors that influence reaction rates (e.g., types of substances involved, temperature, concentration of reactant molecules, amount of contact between reactant molecules)
Level IV (Grade 9-12)
- Knows the structure of an atom (e.g., negative electrons occupy most of the space in the atom; neutrons and positive protons make up the nucleus of the atom; protons and neutrons are almost two thousand times heavier than an electron; the electric force between the nucleus and electrons holds the atom together)
- Knows how the electron configuration of atoms governs the chemical properties of an element as atoms interact with one another by transferring or sharing the outermost electrons
- Knows that the number of electrons in an atom determines whether the atom is electrically neutral or an ion (i.e., electrically neutral atoms contain equal numbers of protons and electrons; a positively charged atom has lost one or more electrons; a negatively charged atom has gained one or more electrons)
- Understands that chemical reactions either release or consume energy (i.e., some changes of atomic or molecular configuration require an input of energy; others release energy)
- Knows that chemical reactions can be accelerated by catalysts (e.g., metallic surfaces, enzymes)
- Knows the variety of structures that may be formed from the bonding of carbon atoms (e.g., synthetic polymers, oils, the large molecules essential to life) and their roles in various chemical reactions, including those required for life processes
- Knows that a large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting ions, molecules, or atoms
- Understands radical reactions and their role in natural and human processes (e.g., ozone and green house gases in the atmosphere; burning and processing of fossil fuels; formation of polymers; explosions)
Physical Sciences Standard 9:
Understands the sources and properties of energy
Level III (Grade 6-8)
- Knows that energy is a property of many substances (e.g., heat energy is in the disorderly motion of molecules and in radiation; chemical energy is in the arrangement of atoms; mechanical energy is in moving bodies or in elastically distorted shapes; electrical energy is in the attraction or repulsion between charges)
- Understands the law of conservation of energy (i.e., energy cannot be created or destroyed but only changed from one form to another)
- Knows that heat energy flows from warmer materials or regions to cooler ones through conduction, convection, and radiation
- Knows how the Sun acts as a major source of energy for changes on the Earth's surface (i.e., the Sun loses energy by emitting light; some of this light is transferred to the Earth in a range of wavelengths including visible light, infrared radiation, and ultraviolet radiation)
- Knows that electrical circuits provide a means of transferring electrical energy to produce heat, light, sound, and chemical changes
- Knows that most chemical and nuclear reactions involve a transfer of energy (e.g., heat, light, mechanical motion, electricity)
- Knows ways in which light interacts with matter (e.g., transmission, including refraction; absorption; scattering, including reflection)
Level IV (Grade 9-12)
- Knows that all energy can be considered to be either kinetic energy (energy of motion), potential energy (depends on relative position), or energy contained by a field (electromagnetic waves)
- Understands the relationship between heat and temperature (heat energy consists of the random motion and vibrations of atoms, molecules, and ions; the higher the temperature, the greater the atomic or molecular motion)
- Knows that nuclear reactions convert a fraction of the mass of interacting particles into energy (fission involves the splitting of a large nucleus into smaller pieces; fusion is the joining of two nuclei at extremely high temperature and pressure) and release much greater amounts of energy than atomic interactions
- Knows that waves (e.g., sound, seismic, water, light) have energy and can transfer energy when they interact with matter
- Knows the range of the electromagnetic spectrum (e.g., radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, gamma rays); electromagnetic waves result when a charged object is accelerated or decelerated, and the energy of electromagnetic waves is carried in packets whose magnitude is inversely proportional to the wavelength
Physical Sciences Standard 10:
Understands forces and motion
Level III (Grade 6-8)
- Understands general concepts related to gravitational force (e.g., every object exerts gravitational force on every other object; this force depends on the mass of the objects and their distance from one another; gravitational force is hard to detect unless at least one of the objects, such as the Earth, has a lot of mass)
- Knows that just as electric currents can produce magnetic forces, magnets can cause electric currents
Level IV (Grade 9-12)
- Knows that magnetic forces are very closely related to electric forces and can be thought of as different aspects of a single electromagnetic force (moving electric charges produce magnetic forces and moving magnets produce electric forces); the interplay of these forces is the basis for electric motors, generators, radio, television, and many other modern technologies
- Knows that nuclear forces are much stronger than electromagnetic forces, which are vastly stronger than gravitational forces; the strength of nuclear forces explains why great amounts of energy are released from the nuclear reactions in atomic or hydrogen bombs, and in the Sun and other stars
- Knows that the strength of the gravitational force between two masses is proportional to the masses and inversely proportional to the square of the distance between them
- Knows that the strength of the electric force between two charged objects is proportional to the charges (opposite charges attract whereas like charges repel) and, as with gravitation, inversely proportional to the square of the distance between them
- Knows that electromagnetic forces exist within and between atoms (e.g., electric forces between oppositely charged electrons and protons hold atoms and molecules together, and are involved in all chemical reactions; electric forces hold solid and liquid materials together and act between objects when they are in contact)
- Knows how different kinds of materials respond to electric forces (e.g., as insulators, semiconductors, conductors, superconductors)
- Knows that materials that contain equal proportions of positive and negative charges are electrically neutral, but a very small excess or deficit of negative charges in a material produces noticeable electric forces
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Selected Standards and Benchmarks
used by permission:
Copyright
2003 McRel
Mid-continent Research for
Education and Learning
2550 S. Parker Road, Suite 500
Aurora, CO 80014
Telephone: (303) 337-0990
www.mcrel.org/standards-benchmarks
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