Will give brainliest for ! 1. the atomic radius increases from top to bottom because more orbitals are added as you go down a group. atomic radius decreases from left to right because there are more protons in each element as you go left to right, increasing the attractions between the protons and electrons, pulling the electrons in closer. a. true b. false

a. True

Explanation:

The atomic radius is taken as the half of the inter nuclear distance between two atoms that are covalently bonded.

Across a period, the atomic radii usually decrease progressively because the nuclear charge(number of protons in the nucleus) increases without the increase in the number of electronic shell. Therefore, the electrons are pulled more to the nucleus.

Down a group, the effect of the nuclear pull is reduced because the number of electron shell increases and the nuclear charge is being compensated for.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.