Question

Bai 1: dot chay m (g) sat trong 4,48 lit khi O2 (dktc) , sau phan ung thu duoc oxit sat tu A, tinh gia tri cua m ?B, tinh khoi luong oxit sat tu thu duoc?Bai 2; nhiet phan hoan toan 15,8 g KMnO4 , sau phan ung thu duoc the tich khi O2 (dktc) la bao n...

Answer 1

Bài 1:

PT: \(3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\)

a, Ta có: \(n_{O_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\)

Theo PT: \(n_{Fe}=\dfrac{3}{2}n_{O_2}=0,3\left(mol\right)\)

\(\Rightarrow m_{Fe}=0,3.56=16,8\left(g\right)\)

b, Theo PT: \(n_{Fe_3O_4}=\dfrac{1}{2}n_{O_2}=0,1\left(mol\right)\)

\(\Rightarrow m_{Fe_3O_4}=0,1.232=23,2\left(g\right)\)

Bài 2:

PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)

Ta có: \(n_{KMnO_4}=\dfrac{15,8}{158}=0,1\left(mol\right)\)

Theo PT: \(n_{O_2}=\dfrac{1}{2}n_{KMnO_4}=0,05\left(mol\right)\)

\(\Rightarrow V_{O_2}=0,05.22,4=1,12\left(l\right)\)

Bạn tham khảo nhé!