Chemistry: Diamagnetic or paramagnetic atoms/ions.?

Question

This is a two part question i'm really stuck on... any help would be greatly appreciated!!

a) Classify the following atoms/ions as either diamagnetic or paramagnetic:
K+ Cr3+ Zn2+ Cd Co3+ Sn2+ Br


b) critique the statements (i.e. state when/if it is correct; if not, why not) "All atoms with an odd atomic number are paramagnetic. All atoms with an even atomic number are diamagnetic."

Thanks!!

Answer 1

Diamagnetic (D) all e⁻s paired; paramagnetic (P) one or more e⁻ unpaired.

K^+ [Ar] 4s^0 D; Cr^3+ [Ar] 3d^3 (↑) (↑)(↑)(0)(0) P; Zn^2+ [Ar] 3d^10 4s^0 D;

Cd(0) [Ar] 4d^10 5s^2 D; Co^3+ [Ar] 3d^6 gas phase: (↓↑) (↑)(↑)(↑)(↑) P; most Co(III) cmplxs

(↓↑) (↓↑)(↓↑).......(0)(0) D; Sn2+ [Kr] 4d^10 4s^2 4p^0 D; Br(0) [Ar] 4d^10 5s^2 5p^5 P.

"All atoms with an odd atomic number are paramagnetic." True. AOs can either be (↓↑) or (↑) hence you can never pair up an odd number of e⁻.

"All atoms with an even atomic number are diamagnetic." False (↓↑) → (↑) (↑) common when the two AOs have the same energy, that is, they are degenerate (Hund's Rule). It occurs for the first time at

C(6e⁻s): [He] 2s^2 2px(↑)py(↑)2pz(0). Due to this fact more atoms are paramagnetic than diamagnetic as the neutral atom in the gas phase: attracted into a magnetic field.

Answer 2

Zn2+ diamagnetic

Co2+ paramagnetic

Cu2+ paramagnetic

Ni2+ paramagnetic



Just understand that if it has a 2+ charge it has 2 less electrons than its natural state. So do the electron configuration and the diagram with the appropriate (2 less spins) electrons. if you have a level with unpaired electrons (spins) then that makes it paramagnetic.

Answer 3

should be : Cr^3+ [Ar] 3d^5 (↑) (↑)(↑)(↑)(↑) -----> P

Answer 4

WHAT IS OXYHEMOGLOBIN