The reaction AB2C (g) <---> B2 (g) + AC (g) reached equilibrium at 900 K in a 5.00 L vessel. At equilibrium 0.0840 mol of AB2C, 0.0350 mol of B2, and 0.0590 mol of AC were detected. What is the equilibrium constant at this temperature for this system?

it's c (engineer's do their work with mechanical stuff not on any living being)

answer carbon and three oxygen atoms;

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.