Question

pleace type the answer

1.Substances are attracted to magnetic field when they experience what types of properties?how nare the electrons paired

2.Spontateity is often diretly associated with the enthaply of a reaction . Explain how an endothermic reaction can be spontateous

Answer 1

Substances for which magnetic susceptibility is positive they are attracted to magnetic properties.they are 1)PARAMAGNETIC substances they have atleast one unpaired electron(permanent magnetic dipoles)in magnetic field theytend to orient them selves parallel to the direction of the field and thus produce magnetism in the substance

FERROMAGNETIC ;show magnetism even in the absence of magnetic field.dipoles are aligned in the same direction.

DIAMAGNETIC;tey are repelled by magnetic field.all are paired electrons.

ANTIFERROMAGNETIC ;this ariseswhen the dipole alignement is zero due to equal opposite alignement.

FERRIMAGNETIC;this arises when there is net dipole moment.

2)Spontaneous reactions are reactions which takes place on their own .In chemistry a chemical reaction is spontanious if the GIBBS FREE ENERGY associated with is negative.G=H-TS; for spontaneous reaction G 0

For an endothermic reaction H is positive .the change in enthalpy of a reaction can be generally understood as the changein the heat of reaction .If the change in enthalpy is ppositive the system absorbs heat energy the reaction is endothermic.example Dissolving table salt in water.the reaction is endothermic and spontaneous at standard temperature and pressure.if the change in entropy at a given temperature is sufficient to over come the unfavourable change in enthalpy then the reaction will spontaneously occur thus endothermic reactions are possible.