Cho O2 thu được mỗi p.ứ là 1 mol
PTHH: 2 KMnO4 -to-> K2MnO4 + MnO2 + O2
2___________________________________1(mol)
2 KClO3 -to-> 2 KCl + 3 O2
2/3________________1(mol)
Ta có: \(\frac{a}{b}=\frac{m_{KClO_3}}{m_{KMnO_4}}=\frac{\frac{2}{3}.122,5}{2.158}=\frac{\frac{245}{3}}{316}=\frac{245}{948}\)