<span> the atmosphere holds about 21 per cent oxygen. Over the Earth’s 4.6 billion year history, oxygen did not appear in the atmosphere until perhaps about 2.5 billion years ago. Since then, oxygen levels have fluctuated in tandem with global geological and biological events, such as mass extinctions.</span>
The reactivity of a metal is determined by how tightly the metal holds onto the electrons in the outermost energy levels (valence electrons)
The molar mass of Li->7g/mol
If 1mol of Li is 7g/mol
1.50mol of Li would be 10.5g/mol
