The answer is the reaction ins a cold pack
2 H₂ + O₂ = 2 H₂O
Answer B only synthesis.
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Noice but I don’t get why was this necessary
Here is your answer

REASON:
Elements which have 4 valence electrons are generally metalloids.
The metalloids show the properties of both metals and non-metals.
We know that,
no. of protons= Atomic number
So,
Atomic no.= 32
Hence,
The element is Germanium which is a metalloid with 4 valence electrons and has 32 protons in nucleus of each atom because it has atomic no. 32
HOPE IT IS USEFUL
I belive this is called condensation.
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