Standards for Teaching and Learning
8.2.1: Explain that all matter is made up of atoms that are far too small to see directly through an optical microscope.
8.2.2: Construct a model of an atom and know the atom is composed of protons, neutrons, and electrons.
8.2.4: Diagram and describe how atoms may combine (bond) into molecules or into large crystalline arrays.
8.2.6: Describe how elements can be classified, based on similar properties, into categories, including highly reactive metals, less reactive metals, highly reactive non-metals, less reactive non-metals, and some almost completely non-reactive (noble) gases.
8.2.7: Understand how an ion is an atom or group of atoms (molecule) that has acquired an electric charge by losing or gaining one or more electrons.
8.2.8: Describe how the atoms, molecules, or ions comprising an object are in constant individual motion, and explain how their average motional (kinetic) energy determines the temperature of the object and how the strength of the forces between them determines the state of matter at that temperature.
8.2.9: Explain that the melting and/or boiling temperature of a substance (element or compound) depend on pressure and are independent of the amount of the sample. (Some materials don't melt and others don't boil because they decompose as the temperature is raised; other materials don't have a sharp melting point because they are not homogeneous.)
8.2.10: Describe the contributions of the scientists involved with the development of current atomic theory, including John Dalton, Marie and Pierre Curie, Joseph John Thomson, Albert Einstein, Max Planck, Ernest Rutherford, Niels Bohr, and Erwin Schroedinger.
8.3.1: Discover and explain how elements and compounds (reactants) react with each other to form products with different properties.
8.3.2: Describe Antoine Lavoisier's work, including the idea that when materials react with each other, many changes can take place, but that in every case the total amount of matter afterward is the same as before (Law of Conservation of Matter).
8.3.3: Explain how the idea of atoms, as proposed by John Dalton, explains the conservation of matter: In chemical reactions, the number of atoms stays the same no matter how they are arranged, and the mass of atoms does not change significantly in chemical reactions, so their total mass stays the same.
8.3.5: Investigate and explain that reactions occur at different rates, slow to fast, and that reaction rates can be changed by changing the concentration of reactants, the temperature, the surface areas of solids and by using a catalyst.
8.3.7: Recognize that indicators of chemical changes include temperature change, the production of a gas, the production of a precipitate, or a color change.
8.4.1: Demonstrate that the mass of an object is a measure of the quantity of matter it contains (measured in kg or g), and its weight (measured in N) is the magnitude of the gravitational force exerted by the Earth on that much mass.
8.4.2: Know density is mass per unit volume.
8.4.3: Investigate and explain that equal volumes of different substances usually have different masses and, therefore, different densities.
8.4.4: Determine and explain that the buoyant force on an object in a fluid is an upward force equal to the weight of the fluid the object has displaced; this principle can be used to predict whether an object will float or sink in a given fluid.
8.4.5: Determine the density of substances (regular and irregular solids, and liquids) from direct measurements of mass and volume, or of volume by water displacement.
8.5.1: Explain how energy is the ability to do work and is measured in joules (J)..
8.5.2: Describe kinetic energy as the energy of motion (e.g., a rolling ball), and potential energy as the energy of position or configuration (e.g., a raised object or a compressed spring).
8.5.3: Investigate and explain how kinetic energy can be transformed into potential energy, and vice versa (e.g., in a bouncing ball).
8.5.4: Recognize and describe that energy is a property of many systems and can take the forms of mechanical motion, gravitational energy, the energy of electrostatic and magnetostatic fields, sound, heat, light (electromagnetic field energy)..
8.5.5: Describe that energy may be stored as potential energy in many ways, including chemical bonds and in the nucleus of atoms.
8.5.6: Explain that the sun emits energy in the form of light and other radiation, and only a tiny fraction of that energy is intercepted by the Earth.
8.5.7: Know the sun's radiation consists of a wide range of wavelengths, mainly visible light and infrared and ultraviolet radiation.
8.5.8: Investigate and explain that heat energy is a common product of an energy transformation, for example, in biological growth, the operation of machines, the operation of a light bulb, and the motion of people.
8.5.9: Explain how electrical energy can be generated using a variety of energy sources and can be transformed into almost any other form of energy, such as mechanical motion, light, sound, or heat.
8.5.10: Investigate and explain that in processes at the scale of atomic size or greater, energy cannot be created or destroyed but only changed from one form into another.
8.5.11: Compare and contrast how heat energy can be transferred through radiation, convection, or conduction.
8.6.1: Investigate and explain that an object can be electrically charged either positively or negatively; objects with like charges repel each other and objects with unlike charges attract each other.
8.6.4: Explain that electrical circuits provide a means of transferring electrical energy from sources such as generators to devices in which heat, light, sound, and chemical changes are produced.
8.6.5: Know power is energy per unit time, expressed in watts, W, and 1 W = 1 J/s. Explain that devices are rated according to their power capacity or consumption.
8.7.1: Recognize that a force has both magnitude and direction.
8.7.2: Observe and explain that when the forces on an object are balanced (equal and opposite forces that add up to zero), the motion of the object does not change.
8.7.3: Explain why an unbalanced force acting on an object changes the object's speed or direction of motion or both.
8.7.4: Explain that every object exerts an attractive gravitational force on every other object.
8.7.5: Know the greater the mass of an object, the more force is needed to change its motion.
8.7.6: Explain that the if the net force acting on an object always acts toward the same center as the object moves, the object's path is a curve about the force center. (Motion in a circular orbit is the simplest case of this situation.)
8.7.7: Graph and interpret distance vs. time graphs for constant speed.
8.8.1: Observe and explain how waves carry energy from one place to another.
8.8.2: Explain how a mechanical wave is a disturbance that propagates through a medium.
8.8.3: Explain how electromagnetic waves differ from mechanical waves in that they do not need a medium for propagation; nevertheless, they can be described by many of the same quantities: amplitude, wavelength, frequency (or period), and wave speed.
8.8.6: Demonstrate that vibrations in materials set up wave disturbances, such as sound and earthquake waves, that spread away from the source.
8.8.7: Recognize that human eyes respond to a narrow range of wavelengths of the electromagnetic spectrum (red through violet) called visible light.
8.8.8: Summarize how something can be "seen" when light waves emitted or reflected by an object enter the eye just as something can be "heard" when sound waves from it enter the ear.
8.8.9: Explain that waves obey the superposition principle: Many waves can pass through the same point at once, and the wave amplitude at that point is the sum of the amplitudes of the individual waves.
Correlation last revised: 1/21/2017