I think that the best phrase to fit into the blank is a "scientific theory".
A scientific theory is developed through experiments which use the scientific method, and a theory can be improved if additional data is available or if people provide suggestions which make the theory fit the data better.
Matter cannot be created or destroyed
Answer:
The activation energy
Explanation:
The activation energy is the energy hump that lies between reactants and products. It is the energy barrier that reactants must cross before they are converted into products.
Based on the collision theory, only particles that possess the activation energy are able to collide in such a way that leads to reaction.
Collision of particles having an energy content less than the activation energy of the reaction merely leads to elastic collision between such particles.
<span>Net Ionic equation: 3Zn^2+(aq) + 2PO4^3-(aq) ---> Zn3(PO4)2 (s)
hope it helps
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The water cycle is one interaction between the geosphere and the cryosphere.