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4.6 CONCEPT ASSESSMENT Suppose that each of these reactions has a 90% yield. CH4(g) + Cl2(g) - CH2Cl(g) + HCl(g) CH3Cl(g) + Cl2(g) - CH2Cl20) + HCl(g) Starting with 50.0 g CH4 in the first reaction and an excess of Cl2(g), the number of grams of CH2Cl2 formed in the second reaction is (a) 50.0 X 0.81 x (85/16) (c) 50.0 X 0.90 X 0.90 (b) 50.0 X 0.90 (d) 50.0 X 0.90 X 0.90 < (16/50.5)(70.9/85)​

User Ammar Bukhari
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1 Answer

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Answer:

212 gm of CH2Cl2 are formed

Step-by-step explanation:

4.6 CONCEPT ASSESSMENT Suppose that each of these reactions has a 90% yield. CH4(g) + Cl2(g) - CH2Cl(g) + HCl(g) CH3Cl(g) + Cl2(g) - CH2Cl20) + HCl(g) Starting with 50.0 g CH4 in the first reaction and an excess of Cl2(g), the number of grams of CH2Cl2 formed in the second reaction is (a) 50.0 X 0.81 x (85/16) (c) 50.0 X 0.90 X 0.90 (b) 50.0 X 0.90 (d) 50.0 X 0.90 X 0.90 < (16/50.5)(70.9/85)​H

1st, rewrite the equations so you can see the problem easier

reaction (1) CH4 +Cl2--------->CH3CL + HCl

reaction (2) CH3Cl + Cl2------> CH2Cl2 + HCl

the product ib reaction (1) is CH3Cl and is formed with a 90% yield.

90% of the reactant methane iis converted to methyk chloride.

methane (CH4) has a molar mass of 12 + 4X1 =16

you start with 50.0 gm of CH4,

SO

50.0/16 =3.125 moles of CH4

90% of this become methyl choride...CH3Cl

SO

0.90 X 3.125 = 2.8 moles of CH3Cl are formed

NOTE 90% HAS ONLY 2 SIGNIFICANT FIGURES SO YOU ARE LIMITED TO 2 SIGNIFICANT FIGURES IN YOUR CALCULATION!

in reaction(2) 1 mole of methyl chloride becomes methyl dichloromethane yi

with again a 90% yield

0.90 X 2.8 = 2.5 moles of CH2Cl2 are formed

so

2.5 moles of CH2Cl2 are formed.

CH2Cl2 has a molar mass of 12 + 2X1 + 2X35.5 =

12 + 2 + 71 =85

1 mole weighs 85 gm

2.5 moles weigh 2.5 X 85 = 212 gm

X

User Rudy Matela
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