Which of the following compounds, on reaction with NaOH and Na2O2, gives yellow colour?

Question

Which of the following compounds, on reaction with NaOH and Na2O2, gives yellow colour? (A)  Zn(OH)2  (B)  Al(OH)3  (C)  Cr(OH)3  (D)  CaCO3

Tardigrade Admin · Accepted Answer

Chromium hydroxide, Cr ( OH )3, when reacts with NaOH and Na 2 O 2, gives sodium chromate, which is yellow in colour. 3Na2O2 + 2Cr(OH)3 arrow underset textyellow2Na2CrO4 + 2H2O + 2NaOH

Q. Which of the following compounds, on reaction with $N a O H$ and $N a_{2} O_{2},$ gives yellow colour?

$Z n (O H)_{2}$

$A l (O H)_{3}$

$C r (O H)_{3}$

$C a C O_{3}$

Chromium hydroxide, $C r (O H)_{3}$ , when reacts with $N a O H$ and $N a_{2} O_{2}$ , gives sodium chromate, which is yellow in colour.
$3 N a_{2} O_{2} + 2 C r (O H)_{3} \to yellow 2 N a_{2} C r O_{4} + 2 H_{2} O + 2 N a O H$

Q. Which of the following compounds, on reaction with NaOH and Na2​O2​, gives yellow colour?

Zn(OH)2​

Al(OH)3​

Cr(OH)3​

CaCO3​