What is the most common element (by mass) forming the planet Earth?
carbon
oxygen
iron
silicon
Iron is most abundant in the Earth's outer and inner core, and it is the fourth most common element in the Earth's crust.
reach: rather globalastronomychemistryEarthelementsgeologytechnology
Answers by country
carbon
oxygen
iron
silicon
answers

16

13

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60

452

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18

43

555

43

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16

39

42

164

7893

293

45

14