Across
- 4. An ion that has a positive charge
- 7. Sublevel energy levels contained within a principal energy level
- 8. Model Model of the atom that describes electrons as traveling in fixed, circular paths—called energy levels or shells—around a central nucleus, much like planets orbiting the sun.
- 9. An ion that has a negative charge
- 15. Atom An atom that has no net electrical charge
- 16. a pure substance that is made up of one type of atom
- 18. (atomic) The quantity of matter contained in an atom of an element, measured in atomic mass units (amu)
- 19. A mathematical wave function that describes the wave-like behavior of an electron in an atom or molecule
- 20. Law Describes a relationship in nature that is supported by many experiments
- 21. A non-charged (neutral) subatomic particle found in the nucleus of an atom, the mass is 1 atomic mass unit (amu); determines the isotope of an element
- 24. The smallest fundamental unit of matter that retains the chemical properties of a specific substance
- 27. Theory A theory of the nature of matter: all material substances are composed of minute particles or atoms of a comparatively small number of kinds and all the atoms of the same kind are uniform in size, weight, and other properties
- 28. Mechanical Model Atomic model in which electrons are treated as waves; also called the wave mechanical model of the atom
- 29. Theory Highly reliable, well established explanation of a natural or physical phenomenon
Down
- 1. Composition The percentage of a sample that is composed of each isotope of an element
- 2. Atomic Mass The average mass of all isotopes of an element, given on the periodic table
- 3. The shortest distance between equivalent points on a continuous wave; is usually expressed in meters,centimeters, or nanometers.
- 5. Atoms of the same element with different numbers of neutrons
- 6. Experiment A classic chemistry/physics experiment where positively charged alpha particles were shot at an ultra-thin sheet of gold foil. The unexpected way the particles scattered proved that atoms are not solid spheres, leading directly to the discovery of the atomic nucleus.
- 10. The positively charged center of an atom, composed of neutrons and protons, and possessing most of the mass but occupying only a small fraction of the volume of the atom
- 11. Detectable events that are observed through the senses or technology; can be explained through scientific laws, ideas, principles, and theories
- 12. Charge A physical property of matter that causes matter to experience a force when placed in an electromagnetic field, can be positive or negative; like charges repel each other and unlike charges attract each other
- 13. Ray Radiation that originates from the cathode and travels to the anode of a cathode-ray tube
- 14. a negatively charged subatomic particle that can be either free (not attached to any atom) or bound to the nucleus of an atom and has negligible mass; determines the chemical reactivity of an element
- 17. Particle Any unit of matter smaller than an atom
- 22. A positively charged subatomic particle found in the nucleus of an atom, the mass is 1 atomic mass unit (amu); determines the identity of an element
- 23. The product of an object's mass and its velocity
- 25. Cloud the system of electrons surrounding the nucleus of an atom
- 26. Principle A broadly accepted, fundamental truth or rule derived from empirical observations
- 27. The smallest particle of an element that retains all the properties of that element; is electrically neutral, spherically shaped, and composed of electrons, protons, and neutrons