Frostbite to the skin and Severe burning to the eyes.
This reaction is called the electrolysis of water. The balanced reaction is:
2H2O = 2H2 + O2
We are given the amount of O2 produced from the electrolysis reaction. This will be the starting point of our calculation.
50.00 grams O2 ( 1 mol O2 / 32 grams O2) ( 2 mol H2O / 1 mol O2) ( 18.01 g H2O / 1 mol H2O ) = 56.28 g H2O
Answer:- 
Explanations:- The first reaction is combustion reaction as the hydrocarbon is burned in presence of oxygen to give carbon dioxide and water.
Second reaction is the synthesis reaction as in general a synthesis reaction looks like:

Third reaction is the decomposition reaction as it looks opposite of synthesis reaction.

In general, a single displacement reaction looks like:

Fourth reaction is single replacement reaction as bromine is replaced by chlorine.
So, the correct choice is the last reaction,
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