Respuesta :

maacastrobr

Answer:

Option D.

Explanation:

  • 6H₂ + P₄ → 4PH₃

First we convert the given reactant masses into moles, using their respective molar masses:

  • 4.00 g H₂ ÷ 2 g/mol = 2 mol H₂
  • 6.20 g P₄ ÷ 124 g/mol = 0.05 mol P₄

0.05 moles of P₄ would react completely with (6*0.05) 0.3 moles of H₂. There are more H₂ moles than required, meaning H₂ is in excess and P₄ is the limiting reactant.

Now we calculate how many PH₃ moles could be formed, using the number of moles of the limiting reactant:

  • 0.05 mol P₄ * [tex]\frac{4molPH_3}{1molP_4}[/tex] = 0.2 mol PH₃

Finally we convert 0.2 mol PH₃ into grams, using its molar mass:

  • 0.2 mol PH₃ * 34 g/mol = 6.8 g

So the correct answer is option D.