Chemical reactions and stoichiometry Q2. Ethylene glycol (C2Hs02) can be produced from the reaction of ethylene oxide (C2H40) and water as shown below. 2H40(g) T 20(g) C2H602(0) If 80 kg/s of C2H40 is mixed with 25.5 lbm/s of water, a) What is the limiting reactant? b) How much ethylene glycol is produced when the reaction is complete? c) How much ethylene glycol is produced if C2H40 is 50% pure

Respuesta :

Answer :

(a) The limiting reactant is, [tex]H_2O[/tex]

(b) The mass of [tex]C_2H_6O_2[/tex] is, 11570 grams

(c) The mass of [tex]C_2H_6O_2[/tex] is, 5785 grams

Explanation : Given,

Molar rate of [tex]C_2H_4O[/tex] = 80 kg/s = 80000 g/s

Molar rate of [tex]H_2O[/tex] = 25.5 lbm/s = 11.57 kg/s = 11570 g/s

conversion used : (1 lbm = 0.453592 kg)

Molar mass of [tex]C_2H_4O[/tex] = 44 g/mole

Molar mass of [tex]H_2O[/tex] = 18 g/mole

Molar mass of [tex]C_2H_6O_2[/tex] = 50 g/mole

First we have to calculate the moles of [tex]C_2H_4O[/tex] and [tex]H_2O[/tex] per second.

[tex]\text{Moles of }C_2H_4O=\frac{\text{Mass of }C_2H_4O}{\text{Molar mass of }C_2H_4O}=\frac{80000g}{44g/mole}=1818.18mole/s[/tex]

[tex]\text{Moles of }H_2O=\frac{\text{Mass of }H_2O}{\text{Molar mass of }H_2O}=\frac{11570g}{50g/mole}=231.4mole/s[/tex]

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

[tex]C_2H_4O(g)+H_2O(g)\rightarrow C_2H_6O_2(g)[/tex]

From the balanced reaction we conclude that

The mole ratio of [tex]C_2H_4O[/tex] and [tex]H_2O[/tex]  is, 1 : 1

From this we conclude that, [tex]C_2H_4O[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]H_2O[/tex] is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of [tex]C_2H_6O_2[/tex].

As, 1 moles of [tex]H_2O[/tex] react to give 6 moles of [tex]C_2H_6O_2[/tex]

So, 231.4 moles of [tex]H_2O[/tex] react to give 231.4 moles of [tex]C_2H_6O_2[/tex]

Now we have to calculate the mass of [tex]C_2H_6O_2[/tex].

[tex]\text{Mass of }C_2H_6O_2=\text{Moles of }C_2H_6O_2\times \text{Molar mass of }H_2O[/tex]

[tex]\text{Mass of }C_2H_6O_2=(231.4mole)\times (50g/mole)=11570g[/tex]

Now we have to calculate the mass of of [tex]C_2H_6O_2[/tex].

As we are given that [tex]C_2H_4O[/tex] is 50 % pure.

So, the mass of [tex]C_2H_4O[/tex] = [tex]11570g\times \frac{50}{100}=5785g[/tex]

The mass of [tex]C_2H_6O_2[/tex] is, 5785 grams