Предмет: Химия, автор: mashayuldashova

Опираясь на мысленный эксперимент докажите, какой из этих веществ находится в какой пробирке: NaCl, NaOH,HCl?

Ответы

Автор ответа: youroxygenium

1

При добавлении к раствору гидроксида натрия фенолфталеина наблюдается окрашивание раствора в малиновый цвет, это связано с тем, что в растворе присутствуют гидроксид-анионы (OH-):

NaOH ⟶ Na(+) + OH(-)

После добавления к раствору гидроксида натрия соляной кислоты наблюдается обесцвечивание раствора, это свидетельствует о том, что в растворе больше не присутствуют гидроксид-анионы, из-за того, что прошла реакция нейтрализации: NaOH + HCl ⟶ NaCl + H2O

H(+) + OH(-) ⟶ H2O

В оставшейся пробирке NaCl

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