<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>
<span>FeNCS+ product...............thats how you do it i believe </span>
Answer:
13.7 moles of O₂ are needed
Explanation:
In order to find the moles of reactants that may react to make the products we need to determine the reaction:
Reactants are hydrogen and oxygen
Product: Water
2 moles of hydrogen can react to 1 mol of oxygen and produce 2 moles of water.
Balanced reaction: 2H₂(g) + O₂(g) → 2H₂O(l)
If 2 moles of hydrogen need 1 mol of oxygen to react
Therefore, 27.4 moles of H₂ must need (27.4 .1) / 2 = 13.7 moles of O₂
