Final answer:
The major product of the reaction mentioned is formed through a double replacement reaction, resulting in green spheres bonding with purple spheres. Given the description of the starting materials and products, this is a synthesis reaction.
Step-by-step explanation:
The predicted major product for the reaction, where cations and anions switch partners, can be found using the concept of double replacement reactions in chemistry. Applying this knowledge to the starting materials which consist of two green spheres bonded together and two purple spheres also bonded, the product of the double replacement reaction would be new compounds where the green sphere is now bonded to a purple sphere.
To classify the reaction, if the starting materials yield more complex products, it is a synthesis reaction. On the other hand, if a complex compound breaks down into simpler products, it's a decomposition reaction. The given examples indicate synthesis reactions where new bonds are formed between different colored spheres representing new compounds.