Describe in your own words what is an air front is

A front is a weather system that is the boundary separating two different types of air. One type of air is usually denser than the other, with different temperatures and different levels of humidity.

- aluminum and copper chloride.

- the chloride ion to separate the aluminum from the oxygen so that the aluminum can react with the copper ions (and the water molecules).

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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