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Bangtan2493
2 năm trước
1) Cho 20,8g hỗn hợp gồm axit axetic và etyl axetat tác dụng vừa đủ với 300g dung dịch NaOH 4%. Phần trăm khối lượng của etyl axetat trong hỗn hợp bằng? 2) Đun 12 gam axit axetic với 9,6 gam ancol metylic ( có H2SO4 đặc làm xúc tác) đến khi phản ứng đạt tới trạng thái cân bằng thu được 11 gam este. Hiệu suất của phản ứng este hoá là
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