Across
- 3. Xe
- 4. A substance which can't be further divided into simpler substances like chemical methods.
- 7. Source of life.
- 8. Rain which has been made more acidic than normal.
- 9. Toxic metal that can cause learning difficulties in children.
- 12. When liquid changes to gas.
- 14. A type of chemical reaction where a compound breaks down into simpler substances.
- 18. A substance formed by the chemical combination of two or more elements in fixed proportions.
- 20. Composes 21% of the atmosphere.
- 25. Type of rock that cover three - quarters of the land surface.
- 26. A state of matter that has a definite shape.
- 29. A common natural gas that is contain in your fart.
- 30. Paper ________ was used to separate solutions of coloured substance.
- 32. A chemical reaction in which a compound is made from its elements.
- 36. U.
- 37. Natural cycle by which rocks are possibly changed into another type of rock by conditions of temperature and pressure.
- 38. The system by which nitrogen and its compound are interchanged.
- 40. It is form from the buried remains of plants and animals.
- 41. Composes 0.04% of the atmosphere.
- 43. Seawater is made drinkable by ________.
- 47. Most reactive group of non-metals.
- 50. A process in which heat energy is produced and released to the surrounding.
- 51. Type of rock form by heat and pressure changing existing rocks.
- 52. A class of chemical element which have a characteristic shiny appearance and are good conductors of heat and electricity.
- 53. A vertical column of the periodic table containing elements with similar properties.
- 55. Sources of energy and other resources which cannot run out.
- 56. The separation of a solid from a liquid, using a fine filter paper which does not allow the solid to pass through.
- 57. The solid substance that has dissolve in liquid to form a solution.
- 59. Substance that can be used as a source of energy.
- 60. First element in the periodic table.
Down
- 1. Atom of the same element which have different numbers of neutrons in their nuclei.
- 2. Changes of physical state from liquid to solid.
- 5. Separating a liquid from a solution.
- 6. A from of calcium carbonate (CaCO3)
- 10. Materials we get from the environment to meet our needs.
- 11. _________ is the process in which plants take in C02 and convert it to sugar.
- 13. Creator of the periodic table.
- 15. A word used to describe the property that metals that can be drawn out and stretched into wires.
- 16. Type of rock form by solidification of melted minerals.
- 17. Mixtures of elements design to have the properties useful for a particular purpose.
- 19. Changes of physical state from solid to liquid.
- 21. Anything which occupies space and has mass.
- 22. The system by which carbon and its compounds in the air ocean and rocks are interchanged.
- 23. A class of chemical element that are typically poor conductors of heat and electricity.
- 24. Zr.
- 27. Harmful effect of human activity and waste.
- 28. Sources of energy that cannot be replaced.
- 31. The system by which water circulates around the earth.
- 33. A direct change of state from solid to gas or gas to solid.
- 34. H20
- 35. Water is a type of this state of matter.
- 39. The ________ is measured by a thermometer.
- 41. Liquéfaction.
- 42. P.
- 44. A subatomic particle that is located in energy levels outside the nucleus.
- 45. Substance which increases the rate of a chemical reaction.
- 46. NH3
- 48. A state of matter that doesn't have a fix volume.
- 49. A horizontal row of the periodic table.
- 51. A word used to describe the property that metals can be bend and beaten into sheets.
- 52. Semi-metal.
- 54. The liquid that dissolves the solid solute to form a solution.
- 58. Our favorite food ;)