Question

for the given reaction P4 + 5O2 gives P4O10.If 31 g of P4 is reacted with excess of oxygen,the percentage yield is 60% then the amount of product formed is
(1).42.6g
2)12.8g
3)71g
4)28.4g
plzzz....answer this....

Answer 1

Answer:

The correct answer is option (A) i.e. 42.6g.

Explanation:

• As per question-

      $P_{4}$  + 5$O_{2}$         -     $P_{4}$$O_{10}$

      31g    Excess            x moles

• As Oxygen is in excess so $P_{4}$  will be the limiting reagent.

So, the number of moles of $P_{4}$  present are -

                  moles= $\frac{weight}{molecularweight}$

                 moles= $\frac{31}{123.89}$   = 0.25

• So, as the coefficient for $P_{4}$ and  $P_{4}$$O_{10}$  are the same. So, the number of moles of  $P_{4}$$O_{10}$  formed theoretically will be 0.25 moles.

•   Note -The percentage yield given is 60% which indicates the whole reactant is not converting into the product as we calculated theoretically.

• So, as per formulae -

  Percentage yield = (Actual yield/Theoretical yield)× 100%

So, to calculate the theoretical yield again we use the formulae to calculate moles.

                                 moles= $\frac{weight}{molecularweight}$

So, putting values as Moles=0.25

                                   The molecular weight of  $P_{4}$$O_{10}$=283.889

                                  Theoretical yield = 70.97g.

                                    Percentage yield= 60% (given)

So, putting these values into the formulae for percentage yield-

we will get Actual yield = 42.6gm which is the amount of product formed.

So, the correct answer is 42.6g i.e. option (A).

#SPJ2

Answer 2

answer is 42.6g

Explanation:

• The given reaction is:

$p4 + 5o2 -> p4o10$

• 1 mole of phosphorous is reacting with 5 moles of oxygen to give one mole of P4O10

• The mass of p4= 4 × 31 = 124g

• The mass of P4O10=4×31+16×10=284g

5. If the yield is 100%, then 31 gm of p4 gives=

$\frac{31 \times 284}{124} = 71g$

of P4O10 ( not to mention)

• now, the percentage of yield is 60%, then the amount of product P4O10 formed
• $71 \times 60\% = 42.6g$