What is the concentration of a solution (in M) prepared by diluting 37.00 mL of 0.250 M potassium chloride to 150.00 mL

the answer for sodium is 0.186

the answer for rubidium is 0.251

the ratio of the conjugate base to the acid required to attain the desired ph.

i believe the answer is three water molecules

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.