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2 năm trước
Hỗn hợp X gồm 0,7 mol C2H5OH và một Axit hữu cơ A có công thức là RCOOH. Cho dung dịch H2SO4 đặc vào X, đun nóng một thời gian thu được hỗn hợp Y. Để trung hòa vừa hết axit dư trong Y cần 200ml dung dịch NaOH 2M. a) Tính hiệu suất PƯ este hóa. b)Biết khi cho 500ml dd NaOH 2M vào Y đến khi PƯ hoàn toàn thu được dd Z. Cô cạn dd Z thu được 84,8 g chất rắn khan. Xác định công thức A. Giúp mình với :(
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