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lehieu_148
2 năm trước
Hợp chất R được tạo bởi nguyên tố Y (hóa trị II) với nhóm (NO3) (hóa trị I). Biết trong R, nguyên tố Y chiếm 34,043% khối lượng. Công thức hóa học của R là A. Zn(NO3)2. B. Cu(NO3)2. C. Ba(NO3)2. D. Mg(NO3)2. ( Làm tự luận hộ mình với ạ )
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