How many moles are in 3.45 g of Na2O?Round your answer to three significant figures. IN A FINAL EXAM HURRY PLEASE

There are 0.056 moles present in 3.45 g of .

Explanation:

Given : Mass = 3.45 g

Moles is the mass of substance divided by its molar mass.

Hence, moles of (molar mass = 61.98 g/mol) is as follows.

Thus, we can conclude that there are 0.056 moles present in 3.45 g of .

the answer is 0.42 is that is an option. this question provides no info

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.