0.269 g of solid sodium hydroxide is placed in a 250-mL volumetric flask. Water is added to dissolve the solid and fill the flask exactly to the mark. What is the molarity of the resulting solution

D. is the answer hope that you

Answer : option a) 84explanation :

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.

Answer///an early form of the atomic theory; dalton atomic theory;

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