Question

In 80 g element X cu masa atomica Ax=40, se afla 96,352 x 10 la 23 electroni s si 144,528 x 10 la 23 electroni p. Indicati configuratia electronica si locul in tabelul periodic si identificati elementul X.

Answer 1

nX = 80/40 = 2 moli de atomi
n (e⁻ s) = 96,352ₓ10²³/(6,022ₓ10²³) = 16 moli
n(e⁻ p) = 144,528ₓ10²³/(6,022ₓ10²³) = 24 moli
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 n e⁻ = 40  moli e⁻
  2 moli atomi X ............contin.................40 moli electroni
    1 atom...................................................x = 40/2 = 20 electroni = Z
1s²2s²2p⁶3s²3p⁶4s²   grupa II A ; perioada a 4-a
element = Ca