The amount of oxygen needed would be 80.19 grams
From the equation of the reaction:
[tex]4NH_3 +3 O_2 --- > 2N_2 + 6H_2O[/tex]
The mole ratio of oxygen and ammonia is 3:4
Mole of 56.8g ammonia = 56.8/17 = 3.34 moles
Equivalent mole of oxygen = 3/4 x 3.34 = 2.5059 moles
Mass of 2.5059 moles oxygen = 2.5059 x 32 = 80.19 grams
More on stoichiometric problems can be found here: https://brainly.com/question/15047541
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