NH4Cl + NaOH = NH3 ↑ + H2O + NaCl 2NH3 + H2SO4 = (NH4)2SO4 (NH4)2SO4 + BaCl2 = BaSO4 ↓ + 2NH4Cl 2NH4[+] + SO4[2-] + Ba[2+] + 2Cl[-] = BaSO4 ↓ + 2NH4[+] + 2Cl[-] SO4[2-] + Ba[2+] = BaSO4 ↓