Which chemical element was discovered first?

Question

Question: Which year were the 118 chemical elements discovered?

Answer 1

List of the chemical elements with the year (sorted in ascending order) when they were first defined as the pure element are as follows: (source)

1. Copper --------> 9000 BC 
2. Lead --------> 7000 BC 
3. Gold --------> Before 6000 BC 
4. Silver --------> Before 5000 BC 
5. Iron --------> Before 5000 BC 
6. Carbon --------> 3750 BC 
7. Tin --------> 3500 BC 
8. Sulfur --------> Before 2000 BC 
9. Mercury --------> 1500 BC 
10. Zinc --------> Before 1000 BC 
11. Platinum --------> c. 600 BC – AD 200 
12. Arsenic --------> Before AD 815 
13. Antimony --------> Before AD 815 
14. Bismuth --------> Before AD 1000 
15. Phosphorus --------> 1669
16. Cobalt --------> 1735
17. Nickel --------> 1751
18. Hydrogen --------> 1766
19. Oxygen --------> 1771
20. Nitrogen --------> 1772
21. Chlorine --------> 1774
22. Manganese --------> 1774
23. Molybdenum --------> 1778
24. Tungsten --------> 1781
25. Tellurium --------> 1782
26. Uranium --------> 1789
27. Titanium --------> 1791
28. Chromium --------> 1797
29. Niobium --------> 1801
30. Tantalum --------> 1802
31. Palladium --------> 1802
32. Cerium --------> 1803
33. Osmium --------> 1803
34. Iridium --------> 1803
35. Rhodium --------> 1804
36. Potassium --------> 1807
37. Sodium --------> 1807
38. Barium --------> 1808
39. Strontium --------> 1808
40. Calcium --------> 1808
41. Magnesium --------> 1808
42. Silicon --------> 1808
43. Aluminium --------> 1808
44. Zirconium --------> 1808
45. Beryllium --------> 1808
46. Boron --------> 1808
47. Yttrium --------> 1808
48. Fluorine --------> 1810
49. Iodine --------> 1811
50. Lithium --------> 1817
51. Cadmium --------> 1817
52. Selenium --------> 1817
53. Bromine --------> 1825
54. Thorium --------> 1829
55. Vanadium --------> 1830
56. Lanthanum --------> 1838
57. Erbium --------> 1843
58. Terbium --------> 1843
59. Ruthenium --------> 1844
60. Caesium --------> 1860
61. Rubidium --------> 1861
62. Thallium --------> 1861
63. Indium --------> 1863
64. Helium --------> 1868
65. Gallium --------> 1875
66. Ytterbium --------> 1878
67. Holmium --------> 1878
68. Thulium --------> 1879
69. Scandium --------> 1879
70. Samarium --------> 1879
71. Gadolinium --------> 1880
72. Praseodymium --------> 1885
73. Neodymium --------> 1885
74. Germanium --------> 1886
75. Dysprosium --------> 1886
76. Argon --------> 1894
77. Europium --------> 1896
78. Krypton --------> 1898
79. Neon --------> 1898
80. Xenon --------> 1898
81. Polonium --------> 1898
82. Radium --------> 1898
83. Radon --------> 1899
84. Actinium --------> 1902
85. Lutetium --------> 1906
86. Protactinium --------> 1913
87. Hafnium --------> 1922
88. Rhenium --------> 1925
89. Technetium --------> 1937
90. Francium --------> 1939
91. Neptunium --------> 1940
92. Astatine --------> 1940
93. Plutonium --------> 1940–1941 
94. Curium --------> 1944
95. Americium --------> 1944
96. Promethium --------> 1945
97. Berkelium --------> 1949
98. Californium --------> 1950
99. Einsteinium --------> 1952
100. Fermium --------> 1952
101. Mendelevium --------> 1955
102. Lawrencium --------> 1961
103. Nobelium --------> 1966
104. Rutherfordium --------> 1969
105. Dubnium --------> 1970
106. Seaborgium --------> 1974
107. Bohrium --------> 1981
108. Meitnerium --------> 1982
109. Hassium --------> 1984
110. Darmstadtium --------> 1994
111. Roentgenium --------> 1994
112. Copernicium --------> 1996
113. Flerovium --------> 1998
114. Livermorium --------> 2000
115. Oganesson --------> 2002
116. Moscovium --------> 2003
117. Nihonium --------> 2003–2004 
118. Tennessine --------> 2009