Answer:
Oxygen
0,108 moles
0g Li; 5,25g of Oâ‚‚; 3,23g of Liâ‚‚O
Explanation:
The reaction is:
4Li + O₂ → 2Li₂O
a) Moles of lithium in 1,50g are:
1,50g × (1mol / 6,941g) = 0,216 moles of Li
Moles of Oâ‚‚ are:
6,98g × (1mol / 32g) = 0,218 moles of O₂
The complete reaction of oxygen requires:
0,218 mol â‚“ (4mol Li / 1 mol Oâ‚‚) = 0,872 moles of Li.
As there are more moles of oxygen than required moles of lithium the reactant in excess is oxygen
b) The limiting reactant is lithium, that means moles of product formed are moles of lithium ÷2, that is, 0,108 moles
a) After the reaction there are 0 moles of Li, 0,218 - 0,216× (1 mol O₂/4 mol Li) = 0,164 moles of O₂ and 0,432 moles of Li₂O. In grams:
0g Li
0,164 mol â‚“ (32g / mol) = 5,25g of Oâ‚‚
0,108mol Liâ‚‚O â‚“ (29,88g / mol) = 3,23g of Liâ‚‚O
To know your answer is right you can sum the initial total mass and must be the same of final total mass
I hope it helps!
