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Câu 1: Dung dịch X chứa NaOH và Ba(OH)2 chưa rõ nồng độ - trung hoà 300ml dung dịch X cần 100ml dung dịch H2SO4 3M. - lấy 300ml dd X tác dụng với dung dịch Fe2(SO4)3 dư thu được kết tủa. a) viết các pthh. Tính nồng độ MOL của các chất trong dung dịch X. Biết tỉ lệ MOL của NaOH và Ba(OH)2 là 2:1. b) lọc lấy toàn bộ kết tủa đem nung ở nhiệt độ cao đến khối lượng không đổi thì thu được bao nhiêu gam chất rắn? Câu 2: Cho 200ml dung dịch X chứa MgCl2 và FeCl3 tác dụng vừa đủ với 500ml dung dịch NaOH 0,3M, thu được kết tủa. Nung kết tủa đến khối lượng không đổi thì được 3,6g chất rắn. a) viết pthh b) tính nồng độ MOL của mỗi muối trong dd X. Các phản ứng xảy ra hoàn toàn. Giải hộ em gấp 2 câu này với ạ
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