23. Solving a chemistry problem

60. A gas containing ammonia was passed through 25 ml of a hydrochloric acid solution with a titer of 0.006970 g / ml. 7.25 ml of sodium hydroxide solution was used for titration of the acid residue. The concentration of sodium hydroxide solution was preliminarily determined, and it was found that 1 ml of NaOH solution is equivalent to 1.021 ml of HCl solution. Calculate the mass of absorbed ammonia.