Answer:
2 N2O5 4 NO2 + 1 O2
Explanation:
For the last one you dont really have to add the 1 but you can if its nedded,
since 3 divided by 3 is 1.
Answer:
it will have 1 valence electron as its in the first group in the periodic table.
It will lose electrons as its easier.
The charge will be 1+ as it lost 1 .
The atomic number is 8
Atomic number=number of proton or number of electrons
Burning a magnesium ribbon in the air is an addition reaction while heating potassium manganate 7 is a decomposition reaction.
<h3>Addition and decomposition reactions</h3>
Magnesium burns in air to produce magnesium oxide as follows:

Potassium manganate 7 burns to produce multiple products as follows:

Thus, the MgO will be heavier than Mg. On the other hand,
will be less heavy than
.
More on reactions can be found here: brainly.com/question/17434463
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