AP EAMCET202119 Aug 2021Morning ShiftChemistryd and f Block ElementsActual
A compound A is used in paints instead of salts of lead. Compound A is obtained when a white compound B is strongly heated. The compound B is insoluble in water but dissolves in NaOH solution, forming a solution of compound C . The compound A on heating with coke gives a volatile metal D and a gas E which burns with a blue flame. Identify the possible species D and C can be respectively?
Options
- AD − Hg   C − Hg ( OH ) 2
- BD − Cd   C − Na 2 CdO 2
- CD − Zn   C − Na 2 ZnO 2
- DD − Zn   C − Zn ( OH ) 2
Correct answer
C. D − Zn   C − Na 2 ZnO 2
Step-by-step solution
Zinc oxide also used in the paints. When zinc hydroxide is heated and formed the zinc oxide and water. Zinc hydroxide is insoluble in water. When zinc hydroxide reacts with the water then it formed the Na 2 ZnO 2 compound. Zinc oxide on heating with carbon gives the compound zinc metal and carbon monoxide gas. Reaction :- Zn OH 2 ( B )   → ∆   ZnO ( A )   + H 2 O Zn OH 2 ( B )   +   NaOH   →   Na 2 ZnO 2   ( C ) ZnO ( A )     +   C   U