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A. Which reactant is the limiting reagent?

b. How much product is formed? (calculate for both if 2)
c. How much of the excess reagent remains?
1) 47.2 g of zinc metal react with 122 g of bromine in a closed container,
Final answers
la.
1b.
1c.

User Qudusayo
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1 Answer

6 votes

Answer:

a. Zinc is the limiting reactant.

b.
m_(ZnBr_2)^(by\ Zn)=162.61gZnBr_2

c.
m_(Br_2)^(leftover)=6.6g

Step-by-step explanation:

Hello there!

a. In this case, when zinc metal reacts with bromine, the following chemical reaction takes place:


Zn+Br_2\rightarrow ZnBr_2

Thus, since zinc and bromine react in a 1:1 mole ratio, we can compute their reacting moles to identify the limiting reactant:


n_(Zn)=47.2g*(1mol)/(65.38g) =0.722molZn\\\\n_(Br_2)=122g*(1mol)/(159.8g) =0.763molBr_2

Thus, since zinc has the fewest moles we infer it is the limiting reactant.

b. Here, we compute the grams of zinc bromide via both reactants:


m_(ZnBr_2)^(by\ Zn)=0.722molZn*(1molZnBr_3)/(1molZn) *(225.22gZnBr_2)/(1molZnBr_2) =162.61gZnBr_2\\\\m_(ZnBr_2)^(by\ Br_2)=0.763molBr_2*(1molZnBr_3)/(1molBr_2) *(225.22gZnBr_2)/(1molZnBr_2) =171.95gZnBr_2

That is why zinc is the limiting reactant, as it yields the fewest moles of zinc bromide product.

c. Here, since just 0.722 mol of bromine would react, we compute the corresponding mass:


m_(Br_2)^(reacted)=0.722molBr_2*(159.8gBr_2)/(1molBr_2) =115.4gBr_2

Thus, the leftover of bromine is:


m_(Br_2)^(leftover)=122g-115.4g\\\\m_(Br_2)^(leftover)=6.6g

Best regards!

User Sportzpikachu
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