Ответ:

CnH2n+1COONa+NaOH=Na2CO3+CnH2n+2

m(CnH2n+2)=5,6*1,965=11г;n(CnH2n+2)=5,6:22,4=0,25моль;

M(CnH2n+2)=11г:0,25моль=44г/моль;

                       12n+2n+2=44

                          14n=44

                            n=3

n(C3H7COONa)=0,25;m(C3H7COONa)=0,25*110=27,5гр.