Critical thinking : Place an unmagnetized piece of iron in a magnetic field (eg iron filings near a magnet). Why is it attracted to the magnet?

Magnets attract iron due to the influence of their magnetic field upon the iron. Before a piece of iron enters the magnet, the polarization of the irons atoms is random. When exposed to the magnetic field, the atoms begin to align their electrons with the flow of the magnetic field, which makes the iron magnetized as well. This, in turn, creates an attraction between the two magnetized objects. This is why a piece of iron that is exposed to a magnet becomes magnetic for some time afterward.

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.