Hi just a reminder don’t click the links, and 11.0 is correct
Answer:

Explanation:
¡Hola!
En este caso, basado en la información dada, es posible conocer la masa de calcio en carbonato de calcio, que de hecho es la misma en la muestra, al utilizar el siguiente esquema de cálculo:

Finalmente, calculamos el porcentaje requerido como sigue:

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Answer:
D 4P +3O₂ → 2 P₂O₃
Explanation:
In this problem, we need to convert the mass of phosphorus and oxygen to moles trying to find the ratio of reaction (The moles of P that reacts per mole of O₂):
<em>Moles P:</em>
12.4g P * (1mol P / 31g) = 0.4 moles
<em>Moles O₂:</em>
9.6g * (1mol / 32g) = 0.3 moles
The ratio of reaction is:
0.4 mol / 0.3 mol = 1.33 = 4 moles of P / 3 moles of O₂
That means 4 moles of P react with 3 moles of O₂ and the reaction that represents this ratio is:
<h3>D 4P +3O₂ → 2 P₂O₃</h3>