Answer:

Explanation:
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In this case, according to the given combustion reaction of octane, it is possible for us to perform the stoichiometric method in order to calculate the mass of octane that is required to consume 300.0 g of oxygen by considering the 2:25 mole ratio, and the molar masses of 114.22 g/mol and 32.00 g/mol respectively:

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There are 4 lone pairs of electrons present in the carbon dioxide molecule
In the reaction Sn(s) + 2H+(aq) → Sn2+ (aq) + H2(g)
from this reaction, we get that Sn loses from 0 to 2 electrons so it's oxidized So it is the reducing agent.
and H gains from 0 to 1 electrons so, it's reduced so ∴ it is the oxidizing agent
Answer:
evaporation or water runoff that's my tips
rain or thunder storm