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Exothermic reactions release heat, causing its temperature to fall. If the reaction is lessening the temperature of the object while releasing all the heat, then you know that the reaction is indeed exothermic. Hope this helps!
Higher humidity because there's more H2O in the air
The ball stops moving because of friction force. Friction is the force that opposes all motion. Therefore, the answer is friction force...
Answer:
Na + H₂O → NaOH + 1/2 H₂
Explanation:
When sodium reacts with water, it forms sodium hydroxide and molecular hydrogen. The unbalanced equation is:
Na + H₂O → NaOH + H₂
We have to balance this equation so it obeys the law of conservation of mass. We have 1 atom of Na on each side and 1 atom of O on each side, so these elements are balanced. However, we have 2 atoms of H on the left side and 3 atoms of H on the right side. The easiest way to balance the H without modifying the other elements is by making 1/2 the stoichiometric coefficient of H₂.
Na + H₂O → NaOH + 1/2 H₂