Chemistry

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Across

1. shared electron pair = ___ pair
3. a polymer is originated from thousands of ___
7. caesium reacts more ___ than rubidium does
9. formula of a stable (2,8,5) molecule
10. widely used to make containers
11. ___ number is the sum of the number of p and n in the atom
13. hazard warning of potassium and sodium, other than flammable
17. the lowest level of crude oil fractions
18. smell of sulphur dioxide
20. plastic foam is produced from polystyrene by adding a foaming ___ while heating it
21. Na burns with ___ yellow flame
23. formula of a stable sulphur molecule
24. crude oil is a mixture of ___ molecules
28. the formula of a covalent compound shows the ___ of one atom to the other(s) in the molecule
31. hazard warning of benzene, tetrachloromethane and asbestos
32. neon glows ___ when electricity passes through it
33. holds 7.3% in nauter (third highest)
36. in the periodic table, elements are arranged in order of ___ order of atomic numbers
37. covalent bond is the strong electrostatic attraction between the shared electrons and two ___ of the bonded atoms
40. covalent bond with three shared electron pairs
42. ___ clothes are made from crude oil fractions
43. short form of what you can do when shopping and buying things
44. structure of He
45. study of substances
46. exception of molecules in compounds
48. the smallest part of an element or a compound which can exist on its own under room conditions
49. bond of C-60 molecule
50. noble gases are ___ gases as they can exist on their own
57. alkaline ___ metal
59. ___ oil is a fuel for heavy vehicles
62. the darker colour it has, the less ___ it is
65. the more easily it flows, the lower ___ it has
66. an atom or a group of atoms having an overall electric charge
67. a metalloid
68. electro. conducts electricity when _?_ or in ___ solution but not in solid state
69. on adding sodium _?_ solution, coloured aqueous solution of halog. turn to ___
71. tin+copper
72. Reduce, reuse and recycle
75. plastics affect the cityscape and environmental ___.
77. Group I elements have low ___ points and boiling points
79. used to describe how the strong force of ionic bond extends
82. plastic ___ take 450 years to decompose
84. crude oil can be separated ___ to different compounds
85. in the formula for electronic arrangement of atoms, n = ___ number
86. a kind of non-metal compounds that can form electro. in water
87. Group I elements are ___ metals that they can be easily cut with a knife
91. stable, barely react
92. to make bristles of toothbrushes, fishing nets, ropes and stockings, etc.
93. the reacitvity of elements ___ down the group
96. fuel for motor cars
97. H2S = ___ _?_
98. elements are classified into ___ and molecules
101. unshared electron pair = ___ pair
102. more than one formula
105. non-metal liquid ion under room conditions
106. different atoms of the same element which have the same number of protons but different number of neutrons
107. ___-60 emits high-energy radiation to kill the micro-organisms in fresh fruits
108. produced in the reaction of lithium and water
111. the same fraction with heavy oil
113. period number = number of ___ electron shells
116. crude oil's separation method belongs to a type of ___ distillation
118. maximum number of electrons in the 4th electron shell
119. electric charge of a radium ion
120. Sn
121. matter can be classified into ___ substances and _?_
123. chemical elements or compounds being able to exist on its own
124. the process of joining many small molecules toether repeatedly to form macro.
129. electro. conducts electricity when ___ or in _?_ solution but not in solid state
131. name of a selenium (Se) ion, which is in group V
133. room temperature (degrees Celcius)
135. action of ___ slowly changed the sea animals and plants' remains into crude oil
136. Mg reacts with ___ to produce hydrogen
139. Group II metals react with dilute ___ acid to form hydrogen
141. the only exception of Group 0 elements
142. lead (II) ___ paper can test for hydrogen sulphide gas
143. ___-135 is used to generate electricity
144. a hydrogen atom has one proton but zero ___
145. we can buy ___ products to reduce the plastic we use by using the same bottle to fill shampoo, etc.
146. ___ petr. gas (LPG)
147. action of placing francium in air for a long time
148. on adding sodium ___ solution, coloured aqueous solution of halog. turn to _?_

Down

1. sodium and potassium form a silvery ___ when they catch water, and move quickly on the water surface
2. atoms are made up of three fundamental "___ particles"
4. production for town gas
5. substances can be classified to conductors, ___ and non-conductors
6. ionic bonding does not take place between two (2,8,18,18,5) atoms because none of them will ___ any electron
8. positively charged ion
9. name of an ion of element P
12. elements cannot be broken down ___, unlike compounds
14. appearance of iodine under room conditions (black ___)
15. ease of evaporation
16. CH4
19. about 199 degrees Celcius of crude oil fractions
22. Cl is a ___ yellow gas
24. crude oil is very difficult to burn directly. A lot of black smoke and many ___ gases are produced in the combustion process
25. potassium has a low ___ that it can float on water surface
26. NaCl is the ___ of two reactants
27. lightest element in Group VII
29. noble
30. reacts steadily with water to form hydrogen
34. relatively odder one in Group II elements
35. suffix for the names of monatomic anions
38. crude oil = ?
39. all halog. have ___ (e.g. fluorine is a pale yellow gas and astatine is a black solid)
41. one of the drawbacks of using plastics (land and water ___)
47. an oil ___ is built to pump the crude oil out
51. metallic filament in light bulbs
52. a chemical bond found only in metals
53. used to make car windows, notice signs and safety goggles
54. H2S = _?_ ___
55. when freshly cut, sodium is shiny, but it ___ easily in air
56. a type of oil where potassium is often stored
58. tennessine (2,8,18,18,32,32,7) is a ___
60. symbol of electron
61. negetively charged ions
63. structure of elements having 8 outermost shell electrons
64. to make shampoo bottles, detergent bottles, waste recycling bins, cling film, plastic bags, etc.
70. covalent bond with one shared electron pairs
73. elements with ___ outmost shell electrons can exist in both atoms and molecules
74. the sound of a silvery sodium ball moving around the water surface
76. chemical bond refers to the strong _?_ attraction, that is, the attracrtion between opposite charges, that holds ___ particles
78. ability to be beaten into thin sheets
80. glucose has 3 ___
81. horizontal row in the Periodic Table
82. litmus paper turns ___ if it is used to test the alkalinity of sodium and water solution
83. ionic compounds are formed by ___ electrons
88. ___-14 dating
89. overall charge of Na₂O
90. plastics shorten the ___ of landfills and reduce land supply
94. ionic compounds are electrically neutral, or ___
95. conduction that involves electro.
99. a thing that forms hydrogen and oxygen when passing through water
100. abbreviation form of polyehylene terephthalete
103. K burns with ___ flame
104. oil ___ is carried out to separate different molecules of crude oil
109. ___ water must be made up of ony non-metals
110. number of elements found naturally
112. polymer such as a polethene molecule
114. chemical bond refers to the strong ___ attraction, that is, the attracrtion between opposite charges, that holds _?_ particles
115. opposite of attraction
117. unit of atmospheric pressure (normally 1)
118. maximum charge of cation
119. general formula for crude oil's CH molecules are CnH(___)
122. gold, silver and copper are ___ elements/ metals
125. caesium,rubidium, etc.
126. opposite of deposition
127. the only non-metal that conducts electricity in solid state without any chemical changes during conduction
128. matter can be classified into _?_ substances and ___
130. Xe
132. exception of molecules in elements other than graph.
134. ___ gas is often found with crude oil
136. covalent compounds are formed by ___ the outermost electrons with each other
137. maximum number of bonding electrons
138. most raw materials for making plastics are ___ from naph.
140. hazard warning of chlorine water