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Mongvanbo
2 năm trước
A và B đều thuộc phân nhóm chính. A tác dụng với HCl giải phóng hidro. Số e lớp ngoài cùng của B bằng số phân lớp e của A. Số hiệu nguyên tử của A gấp 7 lần số hiệu nguyên tử của B. a) Xác định số hiệu nguyên tử của A và B. Viết cấu hình e của chúng. b) A và B có thể tạo được 2 hợp chất X và Y viết CTCT và giải thích liên kết trong X và Y. Nêu cách phân biệt X và Y
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