NaOH. CaO\mathrm{NaOH} \text {. } \mathrm{CaO}NaOH. CaO
Na2CO3\mathrm{Na}_{2} \mathrm{CO}_{3}Na2CO3
CaCO3\mathrm{CaCO}_{3}CaCO3
Ca(OH)2\mathrm{Ca(OH)_2}Ca(OH)2