Across
- 5. each of more than one hundred substances that cannot be interconverted or broken down into simpler substances and are primary constituents of matter. Each element is distinguished by its atomic number i.e the number of protons in the nuclei of its atoms.
- 6. emitting or relating to the emission of ionizing radiation or particles.
- 8. an element whose properties are intermediate between those of metal and solid nonmetals.
- 11. A stable subatomic particle with a charge of negative electricity, found in all atoms and
- 12. A solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity.
- 17. the basic unit of a chemical element.
- 19. not liable to undergo chemical decomposition, radioactive decay, or other physical change.
- 21. A thing that is composed of two or more separate elements; a mixture
- 22. Any of the set of metallic elements occupying a central block in the periodic table.
- 23. a set of elements occupying an entire horizontal row in the periodic table.
- 27. in all atomic nuclei except those of ordinary hydrogen.
- 28. a table of the chemical elements arranged in order of atomic number, usually in rows, so that elements with similar atomic structure appear in vertical columns.
- 29. an atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
- 30. that form strongly acidic compounds with hydrogen from which simple salts can be made.
- 31. a set of elements occupying a column in the periodic table and having broadly similar properties
- 32. a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge
- 34. in magnitude to that of an electron, but of opposite sign.
- 36. of an atom of carbon-12. It is approximately equal to 1.66 x 10^-27 kg.
- 37. a subatomic particle of about the same mass as a proton but without an electric charge
- 38. the sum of the numbers of protons and neutrons in the nucleus of an atom.
- 39. Any of the gaseous elements occupying group 18 of the periodic table.
- 40. Any of the elements occupying group 17 of the periodic table. They are reactive nonmetallic
Down
- 1. A substance made by mixing other substances together.
- 2. property of subatomic particles that causes it to experience a force when placed in an electric and magnetic field.
- 3. each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.
- 4. the quality or character of being periodic; the tendency to recur at intervals.
- 7. a single electron or one of two or more electrons in the outer shell of an atom that is
- 9. a unit of mass used to express atomic and molecular weights, equal to one-twelfth of the
- 10. a fundamental constant that is the smallest known quantity of electricity. Has a value (+or-) of 1.602176634x10^-19 coulombs.
- 13. small, dense region consisting of protons and neutrons at the center of an atom.
- 14. An element or substance that is not a metal.
- 15. for the chemical properties of an atom.
- 16. the system of electrons surrounding the nucleus of an atom.
- 17. as the primary carrier of electricity in solids.
- 18. Any of the reactive elements occupying group 2 of the periodic table.
- 20. Any of the reactive elements occupying group 1 of the periodic table.
- 24. they show variable valence, and a strong tendency to form coordination compounds.
- 25. a theory of matter and energy based on the concept of quanta, especially quantum
- 26. the fixed amount of energy that a system described by quantum mechanics, such as a molecule, an atom, electron, or nucleus, can have.
- 33. the number of a chemical element in the periodic system, whereby the elements are arranged in order of increasing number of protons in the nucleus.
- 35. from their electronic structure.