An electromagnet is the most powerful type of magnet there is. It is a magnet with a current running through it that can be turned on and off .Why might it be useful to be able to turn the electromagnet on and off? to control the strength of the magnet

to reduce wearing out of the magnet over time

to latch onto and let go of objects

to not waste electricity

if you're asking what comes out, it's steam.

the ratio of the conjugate base to the acid required to attain the desired ph.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.