When a book sits on a shelf, what force (if any) does the shelf exert on the book?
a) friction
b) a normal force
c) a action force
d) the weight of the book
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Explain the impact that changing the temperature has on a system in a state of dynamic equilibrium. what will happen when the temperature of an exothermic reaction mixture at equilibrium is increased?

When does phenolphthalein turn pink? in the presence of a base in the presence of an acid when it is in a neutral solution when it is reacting with a metal

Water is called the universal solvent because more substances dissolve in water than in any other chemical. this has to do with the polarity of each water molecule. the hydrogen side of each water (h2o) molecule carries a slight positive electric charge, while the oxygen side carries a slight negative electric charge.