[skeme]

Sulphuryl chloride decomposes as follows

SO2Cl2 (g) → SO2 (g) + Cl2 (g)

0.04 moles of SO2Cl2 are heated at 300°C for 20 minutes The first order rate constant for this reaction under these conditions is 2.1 x 10^-5 s-1

How many moles of reagent remain after 20 minutes?

Assuming that the gases behave perfectly, calculate the volume of the mixture present after 20 minutes of reaction, if the pressure is 1x10^5 Pa

Any help with the above would be much appreciated

[Yggdrasil]

Do you know the integrated rate equation for first order reactions?  If not, look it up (or better yet look up the derivation) in your chemistry text.

[skeme]

Would this work to solve the number of moles of reagent that remain after 20 minutes?

ln (C/0.04) = - (2.1 x 10-5 s-1)(1200sec)

[Yggdrasil]

Yes.