Which of the following statements regarding energy changes during a reaction are true? . 1) if the heat of reaction, δh, is negative, the energy of the products is higher than the energy of the reactants, and the reaction is endothermic.2)two or more atoms must collide, with proper orientation, with energy greater than or equal to the activation energy for a reaction to occur.3)when the activation energy is high, the reaction rate is fast.4) the energy of a collision between atoms or molecules must be greater than the activation energy (ea) for bonds to be broken.

2)Two or more atoms must collide, with proper orientation, with energy greater than or equal to the activation energy for a reaction to occur

Explanation:

Activation energy can be defined as the energy needed in order for a reaction to occur. Activation energy helps to also determine the rate of the reaction that is happening.

When the activation energy of a particular reaction is high, the rate or speed of that reaction tends to be slow while when the activation energy of a particular reaction is low, the rate or speed of that reaction in quite fast.

The Collision theory states that the collision of two or more reactants with the appropriate amount of energy (activation energy) and the proper or right orientation is what causes an effective chemical reaction to occur.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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