Across: |
| 1. | A decomposition that is forced by electricity. E.g. a solution of zinc iodide producing a zinc metal coating at minus pole and brown iodine solution at plus pole | | 2. | The smallest group of atoms which is separable from the most compounds or elemental substances. Examples: H2O, H2O2 | | 5. | It is a reaction where an element substitutes another element from a compound, forming the new compound and liberating the elemental substance. Example: hydrogen + copper oxide --> water + copper | | 6. | Whole of mingled elemental or composed substances, having a variable composition. Ex. Air | | 8. | A reaction among various substances that yelds a single compound substance. E.g. iodine + zinc --> zinc iodide; calcium oxide + water -> calcium hydroxide | | 9. | three-dimensional - continue structure formed by bonded atoms or ions that are regularly displaced in space.
Examples: NaCl (sodium chloride), Silica (silice, SiO2)
| | 10. | An elemental substance not easily workable, with a little capability of conducting electricity and heat. Examples: iodine, carbon, oxygen | | 11. | Is an atom or a group of atoms with an electric charge. Examples: Zinc ion: Zn2+, Iodide: I¯, bicarbonate HCO3¯ | | 15. | It is a substance obtained as the last stage of the decomposition of a compound and it is not further decomposable. Examples: diamond, sulphur | | 16. | That of the zinc is 65,4, that of iodine is 126,9 and that of hydrogen is 1,0 | | 17. | A negatively charged ion. E.g.: I¯ | | 19. | Symbolic representation of a chemical species, from which the constituent elements, the numerical relationship among their atoms, and in some cases, also information on the space disposition, can be derived. Examples: H2O, H2O2 | | 20. | It is a mixture where the single components aren't distinguishable, even if with a microscope, because they are mixed at a very small scale. Examples: oil, sea water | | 21. | A positively charged ion. E.g.: Zn2+ | | 22. | In this mixture the single components are distinguishable either at first sight or with the microscope. Examples: wood, granite, sand | | 23. | A substance in which the constituent elements are present with a constant and prefixed weight ratio. Examples: Cupric oxide | | 24. | It gives the quantity of each component or element as the ratio to the total quantity of solution or compound. Example: stainless steel: 12% chromium, 87,8% iron, 0,2 % carbon; water: 11,2% hydrogen, 88,8% oxygen |
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Down: |
| 1. | It is made up by the same type of atoms present both in the composed substances and in those elemental. Examples. Oxygen in water, in pure oxygen, in air | | 3. | It is a relation among the masses of the elements that combine to form a compound. Examples: 3,9 = iodine : zinc, in zinc iodide; 7,9 = oxygen : hydrogen, in water
| | 4. | from it is not possible to separate other components and its properties are constant and characteristic. Example: oxygen, sodium chloride | | 7. | This technique permits to resolve a mixture in single substances.
Examples: filtration, extraction, crystallization, distillation and chromatography | | 12. | Generally a malleable, good conductor of heat and electricity, substance. Examples: Zn, Cu, Mg | | 13. | It is a reaction that brings the subdivision of a compound in more substances. E.g. oxygen peroxide --> water + oxygen | | 14. | The smallest portion of neutral matter with the characteristics of an element. | | 18. | It is a process in which there are changes in the internal structure of matter, with the formation of one or more new substances |
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