Hà Nguyễn Thị

2 năm trước

Hoà tan một lượng CuO cần 50 ml dung dịch HCl 1M. a) Viết phương trình hoá học của phản ứng. b) Tính khối lượng CuO tham gia phản ứng. c) Tính CM của chất trong dung dịch sau phản ứng. Biết rằng thể tích dung dịch thay đổi không đáng kể. (Biết H = 1, S = 32, O = 16,Cl = 35,5, Cu = 64)

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Phan Kiều Nguyệt Anh

2 năm trước

Đổi 50ml= 0,05

n HCl= 0,05.1=0,05

CuO+ 2HCl ->CuCl2 +H2O

1 2 1 1

0,025 0,05 0,025

m CuO= 0,025.80=2g

CM CuCl2 = 0,025/0,05=0,5M

huynhtruc337

2 năm trước

CuO + 2HCl ==> CuCl2 + H2O

0,025...0,05............0,025

nHCl= 0,05x1= 0,05 (mol)

==> mCuO= 0,025x80= 2 (g)

CmCuCl2=n/V= 0,025/0,05= 0,5M

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