Câu 16: hòa tan hoàn toàn 2,8g sắt vào dung dịch axit clohidric (HCl), thu đc muối sắt (II) clorua và giải phóng khí hidro (đktc) a) tính thể tích khí hiđrô thoát ra b) tính khối lượng muối tạo thành sau phản ứng c) nếu đem toàn bộ lượng khí hiđrô thoát ra ở trên đi qua bật đồng (II) oxit nung nóng thì thu đc bao nhiêu gam đồng

2 câu trả lời

Bạn tham khảo:

$Fe+2HCl \to FeCl_2+H_2$

$a/$

$n_{Fe}=\dfrac{2,8}{56}=0,05(mol)$

$n_{Fe}=n_{H_2}=0,05(mol)$

$V_{H_2}=0,05.22,4=1,12(l)$

$b/$

$n_{FeCl_2}=n_{Fe}=0,05(mol)$

$m_{FeCl_2}=0,05.127=6,35(g)$

$c/$

$CuO+H_2 \xrightarrow{t^{o}} Cu+H_2O$

$n_{Cu}=n_{H_2}=0,05(mol)$

$m_{Cu}=0,05.64=3,2(g)$

Đáp án:

 

Giải thích các bước giải:

 Ta có: nFe = 2,8/56 = 0,05 (mol)

PT: Fe+2HCl ---> FeCl2 +H2

___0,05_____________0,05__0,05 (mol)

a, V(H2) = 0,05.22,4 = 1,12 (l)

b, mFeCl2 = 0,05.127 = 6,35 (g)

c, PT: CuO+H2 ---to---> Cu+H2O

_____________0,05__________0,05 (mol)

=> mCu = 0,05.64 = 3,2 (g)

Bạn tham khảo nhé!

Câu hỏi trong lớp Xem thêm

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