em cần gấp lắm r ạ Câu 1/ cho m gam hỗn hợp kim loại AL, Cu tác dụng với dung dịch H2SO4 loãng lấy dư, sau khi phản ứng kết thúc thu đc 13,44 lít khí ở đktc và chất rắn ko tan. Lấy phần chất rắn ko tan đem tắc dụng hết axit sunfuric đặc, nóng. Sâu phản ứng thu đc 6,72lits khí SO2 (đktc) a/ Viết phương trình hóa học xẩy ra b/ Tính m c/ Tính % khối lượng mỗi kim loại trong hỗn hợp Câu 2 cho 200gam dung dịch sắt 2 clorua nồng độ a%. Tác dụng vừa đủ vs 100ml dung dịch NaOH 1M, KOH 1,5M.Sau phản ứng thu đc kết tủa X. Nung X trong không khí đến khối lượng ko đổi thu đc m gam rắn Y a/ Tính a b/ Tính m Câu 3 cho 8 gam hổn hợp Mg., Fe tan hết trong 200 gam dung dịch H2SO4 loãng. Sau phản ứng thu đc 4,48 lít khí H2 (đktc) a/ Tính % khối lượng mỗi kim loại trong hổn hợp ban đầu b/ tính nồng độ % axit đã dùng

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