30 points. !
which is greater, the atomic radius of krypton (kr), or the ionic radius of strontium cation (sr^2+)? justify your answer in terms of nuclear charge, effective nuclear charge (z_eff), number of principle energy levels, and the shielding effect.

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.

How many oxygen atoms are there in 3.15 moles of hcl manganese (iv) oxide, mno2