Answer: both options A and D
Explanation:
Half filled and completely filled orbitals are more stable than any other configuration since they are more symmetrical and energy exchange Occurs readily.
So 4f^7& 4f^14 are more stable
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Molar mass ( CuSO₄) = 159.609 g/mol
159.609 g ----------------- 6.02 x 10²³ molecules
? g ------------------ 3.36 x 10²³ molecules
mass = ( 3.36 x10²³) x 159.609 / 6.02 x 10²³
mass = 5.36 x 10²⁴ / 6.02 x 10²³
mass = 8.90 g
hope this helps!
For example...
You have solution with [H+] = 0,01M
>>>> pH = -log[H+] = -log0,01 = 2
And you increase the [H+] by 10x ---> 0,01×10 = 0,1M
>>>> pH = -log0,1 = 1
○ pH decrease by 2x
○ pH is more acidic