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The decomposition reaction of carbon disulfide to carbon monosulfide and sulfur is first order with k = 2.80 ✕ ✕ 10−7 sec-1 at 1000°c. cs2(g) → cs(g) + s(g)

a. how much of a 4.83-gram sample of carbon disulfide would remain after 37.0 days? 1.97 1.97 grams carbon disulfide
b. how much carbon monosulfide would be formed after 37.0 days? 1.14 1.65 grams carbon monosulfide useful information 1.013 bar = 760 torr = 1 atm = 760 mm hg

1 Answer

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Answer: a) 1.97 grams of carbon disulfide will remain after 37.0 days.

b) 2.85 grams of carbon monosulfide will be formed after 37.0 days.

Step-by-step explanation: The decomposition of carbon disulfide is given as:


CS_2(g)\rightarrow CS(g)+S(g)

at t=0 4.83g 0 0

at t=37 days 4.83 - x x x

here,

x = amount of
CS_2 utilised in the reaction

This reaction follows first order kinetics so the rate law equation is:


k=(2.303)/(t)log(A_o)/(A)

where, k = rate constant

t = time


A_o = Initial mass of reactant

A = Final mass of reactant

a) For this, the value of


k=2.80*10^(-7)sec^(-1)

t = 370 days = 3196800 sec


A_o = 4.83

A = 4.83-x

Putting values in the above equation, we get


2.8* 10^(-7)sec^(-1)=(2.303)/(3196800sec)log\left((4.83)/(4.83-x)\right)

x = 2.85g

Amount of
CS_2 remained after 37 days = 4.83 - x

= 1.97g

b) Amount of carbon monosulfide formed will be equal to "x" only which we have calculated in the previous part.

Amount of carbon monosulfide formed = 2.85g

User Daniel Crenna
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