2Al + 3ZnCl₂ ----> 3Zn + 2AlCl₃
What is the coefficient in front of AlCl₃? ==>> 2
(2) 2 - 7 - 18 - 7 does, because the electron from the L shell jumped to the N shell, which requires energy.
The rest of them are either different types of atoms (different elements) or are not the excited state (ground state)
Answer: Fireworks exploding is a chemical change.
Explanation: Lighting gunpowder, and making the explosion is a chemical change.
They rely on scientists for facts and answers
<span> The body has to do this to make sure and or to prevent damage to the delicate tissues that form the Respiratory System. This is important because </span>Your body's organs, such as your heart and brain, need oxygen-rich blood to work well. (if it gets damaged by the Cold/Dry air you breath in on a daily)<span><span>Respiratory failure </span>also can occur if
your lungs can't properly remove carbon dioxide (a waste gas) from your
blood. Too much carbon dioxide in your blood can harm your body's
organs.
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