CH3OH+C3H7OH=C3H7OCH3+H2O    (катализатор H2SO4)

n CH3OH=16/32=0.5 моль

n C3H7OH=22.5/60=0.375 моль

n  C3H7OCH3=0.375*80%=0.3моль

m  C3H7OCH3=0.3*74=22.2 г 

Как то так...

                                CH3OH+ CH3-CH(OH)-CH3 = CH3-O-CH-CH3 +H2O

                                     1                        1                                1           |

                                                                                                           CH3

n(CH3OH)=16/32=0,5моль;

n(CH3-CH(OH)-CH3)=22,5/60=0,375моль;

метанол в избытке!          Значит , n(эфира) =0,375г;  m(эфира) =0,375*74=27,75г.

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