Đổi 672ml = 0,672 lít
Ta có: \(n_{O_2}=\dfrac{0,672}{22,4}=0,03\left(mol\right)\)
PTHH: \(2KClO_3\xrightarrow[t^o]{MnO_2}2KCl+3O_2\)
a. Theo PT: \(n_{KClO_3}=\dfrac{2}{3}.n_{O_2}=\dfrac{2}{3}.0,03=0,02\left(mol\right)\)
=> \(m_{KClO_3}=0,02.122,5=2,45\left(g\right)\)
b. Theo PT: \(n_{KCl}=n_{KClO_3}=0,02\left(mol\right)\)
=> \(m_{KCl}=0,02.74,5=1,49\left(g\right)\)