Pointers to Review for Second Periodical Test PDF

POINTERS TO REVIEW FOR THE SECOND PERIODICAL TEST 1. Copper and aluminum are used in cooking pans and pots because they are good conductors of heat. 2. When oxygen combines with magnesium, it tends to share two electrons. 3. Covalent compounds do not conduct electricity when dissolved...

POINTERS TO REVIEW FOR THE SECOND PERIODICAL TEST 1. Copper and aluminum are used in cooking pans and pots because they are good conductors of heat. 2. When oxygen combines with magnesium, it tends to share two electrons. 3. Covalent compounds do not conduct electricity when dissolved in water because covalent compounds are weakly bonded. 4. Vinegar, liquefied petroleum gas in a tank, and nail polish remover are examples of organic compounds. 5. Organic compounds contain carbon; they can be produced by living things, and they can be produced artificially. 6. Butane, which is a hydrocarbon, is consists of 4 atoms of carbon and 10 atoms of hydrogen. (CH~3~CH~2~CH~2~CH~3~) 7. The presence of double bonds is the most important characteristic of alkenes that makes them different from other hydrocarbons. 8. Cooking gas or liquefied petroleum gas is a mixture of C~3~H~8~ and C~4~H~10~. They are propane and butane. 9. Isomers are organic compounds that contain the same functional groups but differ in their connectivity or spatial arrangement. 10. Propene is a hydrocarbon that contains double bond within the atom. 11. When calcium carbide is dropped in water, it produces acetylene that can be used for melting metals. 12. The functions of carbonyl compounds may include: as cleaning agent, preserving organic compounds, and embalming human cadevers. 13. Carbon monoxide is a toxic gas, a dangerous gas that can be produced from the combustion of hydrocarbons if there is inadequate supply of oxygen. 14. Acetone is an organic compound that can be used as a solvent in the pharmaceutical industry. 15. Organic compounds like kerosene and liquefied petroleum gas are highly flammable. 16. Kerosene can be used for cooking foods. 17. Lubricating oil can be used to minimize or reduce friction to the ball bearings of the wheels of a bicycle. 18. One mole of a substance contains Avogadro's number equal to 6.02 x 10^23^. 19. One example of the application of the concept of the mole in determining the mass of a substance is this: A student calculates the number of moles of water molecules in a given substance. 20. The unit of measure used to represent the amount or quantity of a substance is mol. 21. The chemical formula of washing soda or sodium carbonate is Na~2~CO~3~. Its formula mass is 106 g/mol. 22. The percentage mass of P in H~3~PO~4~ (Phosphoric acid) is 31.6 %. 23. The term molecular mass is used for covalent compound. 24. The molecular mass of acetone ((CH~3~)~2~CO) is 58 g/mol. 25. A silicon chip in an integrated circuit of a computer has a mass of 6.2 grams. The number of moles of silicon in the chip in this case is o.22 mole, and the number of silicon atoms in the chip is 1.3 x 10 ^-25^ atoms. 26. The molar mass of a compound is the sum of the molar masses of its element. 27. The molecular mass of water is 18 g/mol. A 6 grams of water contains 0.33 mol. 28. The number of atoms of sulfur in Al(S~2~O~3~)~3~ is six. 29. Democritus was one of the Greek philosophers who thought that matter is made up of uncuttable particles called atomos. 30. When nonmetals become anions, they gain electrons. 31. As the atomic number of the elements in period 3 increases, the electronegativity generally also increases. 32. The number of electron pairs shared between Carbon and Oxygen in carbon dioxide molecule is two. 33. Ionic compounds are soluble in water. 34. When fluorine combines with oxygen, it tends to share electrons. 35. Ductility is the ability of metals to be drawn into fine wires. 36. The symbol for carbon is C; for calcium is Ca; for copper is Cu; and for cobalt is Co. 37. There is a metallic bond in a silver bracelet, aluminum foil, and iron steel. 38. The last sublevel of energy that the atom Boron occupy is the p. 39. The element argon is a noble gas which mean it has a stable electron configuration. 40. The atomic number of an element indicates the number of protons in the nucleus of an atom.