The reaction is a synthesis…

… because <em>two substances are combining to make one other substance</em>.

It is also a <em>reduction-oxidation reaction</em> because the <em>oxidation number of Al increases</em> from 0 to +3 and the <em>oxidation number of O</em> decreases from 0 to -2.
Simple 6L of air times the .21L of O2 = 1.26
<span>Answer: The 1 kg of water will reach the lowest temperature
</span>
Both of the objects is water so their specific heat should be same. The heat removed from the 2kg of water which is 2 times of mass than the 1kg water. Since the heat removed, both of their temperatures will drops. But 2kg water temperature drops will be half of 1kg water.
The formal charge on each atom can be known by counting up the number of valence electrons that is present on each atom.
<h3>What is Lewis structure?</h3>
The term Lewis structure is the representation of a compound using its symbols and showing the valence electrons as dots. This question is incomplete as the Lewis structures were not shown.
If it is shown, we can know the formal charge on each atom by counting up the number of valence electrons that is present on each atom.
Learn more about Lewis structure: brainly.com/question/4144781