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Nitrogen is a chemical element and a gas that constitutes how much of the volume of the Earth's atmosphere?
78%
Palladium is a chemical element that is used, among others, in what field?
Electronics
Silver is a chemical element with the chemical symbol?
Ag
What is the chemical symbol of mercury?
Hg
What kind of chemical element is radon?
Noble gas
Which chemical element has the chemical symbol Ca?
Calcium
Which of these chemical elements is not vital for the human body?
Thallium
Which of these chemical elements is the mineral that is the hardest?
Boron
Which of these chemical elements is used in medication for manic depressives?
Lithium
Which of these is not the name of a chemical element?
Delerium