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duyyenson113
2 năm trước
Câu 1: cho 11,2 g sắt tác dụng vừa đủ với HCl. Sau phản ứng thu đc với V lít khí hiđro ở đktc? a) Tìm V. b) Tìm khối lượng của FeCl2 tạo ra sau phản ứng? c) Tìm khối lượng của HCl Câu 2: Xác định các công thức hóa học của các oxit sau? a) Biết phân tử khối của oxit là 80 và thành phần % S=40%. b) biết thành phần %Fe=70% và phân tử khối của oxit là 160. Câu 3: Một oxit của nitơ có tỉ lệ vệ khối lượng của nitơ đối với oxi 7:20. Tìm công thức của oxit. Câu 4: Xác định công thức hóa học của một oxit nhôm biết tỉ lệ khối lượng của hai nguyên tố nhôm và oxi là 4,5:4.
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