Question

12 multiple choice 1 point
chemical equations always include an arrow signifying what?
the direction of the reaction.
the size of the reaction.
how fast the reaction is moving.
the importance of the reaction.
13 multiple choice 1 point
every chemical reaction will have ____ and ____.
liquids; solids
reactants; products
water; heat
combustion; photosynthesis

Explanation:

Question 12

In chemical equations, the arrow is used to show the direction in which the reaction proceeds (reactants to products). The "size" of a reaction isn't indicated by the arrow, reaction rate is about kinetics (not the arrow), and importance isn't signified by the arrow. So the correct option is the one about the direction of the reaction.

A chemical reaction involves reactants (substances that react) being transformed into products (substances formed). Not all reactions have liquids/solids, water/heat, or are combustion/photosynthesis. So the correct pair is reactants and products.

Answer:

A. the direction of the reaction.

Question 13