Answer:
May be third one because of the formation of H2(hydrogen)on the product side.
Answer:
4.25% is the final concentration of phosphoric acid.
Explanation:
Initial concentration of phosphoric acid = 
Initial volume of phosphoric acid = 
Final concentration of phosphoric acid = 
Final volume of phosphoric acid = 
( 1L = 1000 mL)



4.25% is the final concentration of phosphoric acid.
1,2,1,4 are your coefficients
Answer:
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