At a certain temperature this reaction follows first-order kinetics with a rate constant of 0.0197s. 2N2O5 (g) right arrow 2N2O4 (g) + O2 (g)Suppose a vessel contains N2O5 at a concentration of 0.280 M. Calculate how long it takes for the concentration of N2Os to decrease by 0.0476 M. You may assume no other reaction is important.

Explanation:

Hello,

In this case, for first-order kinetics we have an integrated rate law of this reaction as:

Thus, we compute the time for an initial concentration of 0.280 M which ends up in 0.0476 M as shown below:

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considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.