2KOH + Al2O3 = 2KAlO2 + H2O2KOH + SO3 = K2SO4 + H2O2KOH + H2SO4 = K2SO4 + 2H2O2K[+] + 2OH[-] + 2H[+] + SO4[2-] = 2K[+] + SO4[2-] + 2H2O2H[+] + 2OH[-] =2H2O2KOH + CuSO4 = Cu(OH)2↓ + K2SO42K[+] + 2OH + Cu[2+] + SO4[2-] = Cu(OH)2↓ + 2K[+] + SO4[2-]Cu[2+] + 2OH = Cu(OH)2↓Al2O3 + 3SO3 = Al2(SO4)3Al2O3 + 3H2SO4 = Al2(SO4)3 + 3H2OAl2O3 + 3H[+] + SO4[2-] = 2Al[3+] + 3SO4[2-] + 3H2OAl2O3 + 3H[+] = 2Al[3+] + 3H2OH2SO4 + Cr = CrSO4 + H2↑H2SO4 + 2AgNO3 = Ag2SO4 ↓+ 2HNO32H[+] + SO4[2-] + 2Ag[+] + 2NO3[-] = Ag2SO4 ↓+ 2H[+] + 2NO3[-]2Ag[+] + SO4[2-] = Ag2SO4 ↓CuSO4 + Cr = Cu + CrSO4Na2S + 2AgNO3 = Ag2S↓ + 2NaNO32Na[+] + S[2-] + 2Ag[+] + 2NO3[-] = Ag2S↓ + 2Na[+] + 2NO3[-]2Ag[+] + S[2-] = Ag2S↓