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linh26pbh
2 năm trước
Bài 6: Canxi cacbonat CaCO3 là thành phần chính của đá vôi, khi nung đá vôi sẽ xảy ra phản ứng hóa học sau: CaCO3 -----> CaO + CO2 a/ Viết PTHH từ sơ đồ trên? b/ Tính thành phần % theo khối lượng của CaCO3 có trong đá vôi biết rằng khi nung 280 kg đá vôi thì tạo ra 140 kg CaO và 110 kg CO2? Bài 7: Đốt cháy x gam photpho bằng y lit khí oxi ở đktc thì phản ứng xảy ra hoàn toàn, chỉ tạo ra duy nhất 35,5 gam Điphotpho pentaoxit. Hãy chọn câu đúng trong các câu kết quả sau và giải thích? a/ x = 15 ; y = 16 b/ x = 30 ; y = 5,5 c/ x = 15,5 ; y = 14
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