Which statement describes a major drawback of the Bohr model that caused scientists to replace it? It worked only for helium and larger atoms.
It did not identify the distance between an electron and the nucleus.
It contradicted the Heisenberg uncertainty principle.
It stated that spectral lines of atoms are similar.

your answer is option A hope ur help and mark me brainlist

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.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.