Step 1: 2A⟶B+C slow Step 2: B+C⟶E fast Overall: 2A⟶E Determine the rate law for the overall reaction, where the overall rate constant is represented as .

Explanation:

Steps mention in question are as follow.

Step 1: 2A <> B ( fast)

Step 2: B + C > D (slow)

Overall: 2A + C > D

The slowest step is as follows

2A <> B

Since the rate law is written as concentrations of reactants raised to power their stoichiometric coefficient multiplied by rate constant. Thus, rate law for this reaction can be written as follow.

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a

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.