Question

question 2
how can you tell if an element is paramagnetic (weakly attracted to magnetic field) or diamagnetic (repelled by magnetic field)?
(reference p 299 of your textbook.)
a unpaired electrons in the valence electrons means paramagnetic, paired means diamagnetic.
b unpaired electrons mean the substance is paramagnetic, paired means diamagnetic.
c unpaired electrons in the valence electrons means diamagnetic, paired means paramagnetic.
d unpaired electrons mean the substance is diamagnetic, paired means paramagnetic.

Explanation:

Paramagnetism occurs when there are unpaired electrons in an atom or molecule. These unpaired electrons have a magnetic moment that can align with an external magnetic field, causing the substance to be weakly attracted to the field. Diamagnetism, on the other hand, occurs when all electrons are paired. Paired electrons have magnetic moments that cancel each other out, resulting in a net magnetic moment of zero. When an external magnetic field is applied, a weak induced magnetic moment is created that opposes the external field, causing the substance to be repelled. It is not just the valence electrons but all electrons in the atom or molecule that determine paramagnetism or diamagnetism. So, unpaired electrons (regardless of being in valence or inner - shells) mean the substance is paramagnetic and paired electrons mean diamagnetic.

Answer:

B. Unpaired electrons mean the substance is paramagnetic, paired means diamagnetic.