CH3OH(HBr) → X1(NH3) → X2(HBr) → X3(KOH) → X2 → N2

m(h3po4) = 3+31+64=108

m(h2o) = 2+16=18

5 молекул h3po4 = 108*5=540

10 молекул h20 = 18 * 10=180 =>

540/180 = 3

ответ : в три раза 

h2o . 1*2+16*1=18 . 7/2=x/18 x=7/2*18=63

cnh2n+h2=cnh2n+2

4.48: 22.4=0.2моль

14: 0,2=70

14n=70

n=5

c5h10