Question

When phosphorus reacts with chlorine, phosphorus trichloride is formed according to the equation

_____P_{4}(s) + _____Cl_{2}(g) → _____PCl_{3}(l)(unbalanced)


A) Balance the equation by filling in the correct coefficients in the equation above.


B) Determine how many grams of chlorine gas Cl_{2} would be required to react with 10.6 g of phosphorous P_{4}(Mw(P_{4})= 123.9g/mol;Mw(Cl_{2})= 70.9 g/mol. Your answer should be gram chlorine gas Cl_{2})

Answer 1

Mass = 38.3 g

Step-by-step explanation:

Given data:

Mass of Cl₂ required = ?

Mass of phosphorus = 10.6 g

Solution:

Chemical equation:

P₄ + 6Cl₂ → 4PCl₃

Number of moles of P₄:

Number of moles = mass/ molar mass

Number of moles = 10.6 g/123.9 g/mol

Number of moles = 0.09 mol

Now we will compare the moles of P₄ with Cl₂ from balance chemical equation.

P₄ : Cl₂

1 : 6

0.09 : 6×0.09 = 0.54 mol

Mass of chlorine gas:

Mass = number of moles × molar mass

Mass = 0.54 mol × 70.9 g/mol

Mass = 38.3 g