Предмет: Химия, автор: user272727

Визначте об'єм розчину етанолу з масовою часткою спирту 96%(густина 0,8г/мл), який необхідний для естерифікації аміно-оцтової кислоти масою 37,5.

Ответы

Автор ответа: anastasiaz16y

Ответ:

NH2CH2COOH+C2H5OH=NH2CH2COOC2H5+H2O

Моль этанола 2*12+16+6*1=46г

Моль аминоуксусной кислоты 2*12+2*16+1*14+5*1=75г

Взято 37,5/0,75=0,5 моля аминоуксусной кислоты

По реакции:

1 моль аминоуксусной кислоты реагирует с 1 молем этанола

0,5 - х

х=0,5*1/1=0,5 моля этанола

Необходимо 46*0,5=23 г этанола

Тогда раствора с массовой долей 96% потребуется:

23*100/96=24 г (округленно!) ,

а объем такого раствора составит (m=V*p, отсюда V=m/p):

24/0,8=30 мл

Ответ: Необходимо взять 30 мл 96% раствора этанола.

Объяснение:

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