Aluminum (Al) reacts with sulfuric acid, H2SO4, which is the acid in an automobile batties, according to the equation : 2Al + 3H2SO4 → Al2 (SO4)3 + 3H2

If 20.0 grams Al is put into a solution containing 115 g of H2SO4.

a. Which of the reactants is the limiting reagent?
b. How many grams of Al2 (So4) will be be formed?
c. How many grams of the reactant in excess will be left over?
d. How many moles of H2 will be formed?

the answer is learned

a electronegativity decreases beacuse the size of nucleus is bigger.

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

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.