Answer:
0.877 M
Step-by-step explanation:
Number of moles of ammonia = 0.879 g /17 g/mol = 0.05 moles
The reaction equation is ;
2NH3 + OBr-→ N2H4 + Br- + H2O
2 moles of NH3 reacts with 1 mole of hypobromite
0.05 moles of NH3 reacts with 0.05 moles ×1 mole/2 moles
= 0.025 moles
Number of moles = concentration × volume
Concentration = Number of moles / volume
Concentration = 0.025 moles × 1000/28.5
Concentration = 0.877 M