What is the mole ratio needed to determine the mass of phosphorus trifluoride produced from the reaction of 120 g of phosphorus with excess fluorine?

Answer:
[tex]\frac{4molPF_3}{1molP_4}[/tex]
Explanation:
Hello
In this case, given the reaction:
[tex]P_4(s)+6F_2(g)\rightarrow 4PF_3(g)[/tex]
It means that since the coefficients preceding phosphorous and phosphorous trifluoride are 1 and 4, the correct mole ratio should be:
[tex]\frac{4molPF_3}{1molP_4}[/tex]
Because given the mass of phosphorous it is convenient to convert it to moles and then cancel it out with the moles on bottom of the mole ratio.
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