A reversible reaction is where the products of the reaction can themselves react to produce the original reactants.
In other words: A+B <==> C+D or A and B react to produce C and D
C and D react to produce A and B
Also Fairly Easy:-
When A and B react their concentrations fall, (think about it, there's less of them because they're being used in reactions) so this means a lower reaction rate, a slower forward reaction. However, as A and B have been reacting into C and D there is now a higher concentration of them. C and D react to form A and B faster, due to the high concentration and there is a faster backward reaction.
After a while...
Eventually this balances and the reaction rates equal one another, this is equilibrium (did you guess it from the name?). This leaves no overall…