Eduprobe
Question:
Which of the following statements is incorrect?
Pure sodium metal dissolves in liquid ammonia to give blue solution
NaOH reacts with glass to give sodium silicate
Aluminium reacts with excess NaOH to give Al(OH)3
NaHCO3 on heating gives Na2CO3
Solution:
(A) Pure sodium metal dissolves in liquid ammonia to give a blue solution. The blue color is due to the formation of ammoniated electrons. Na + liq NH3 ↔ Na+(ammoniated) + e-(ammoniated) blue
(B) NaOH reacts with glass to give sodium silicate. Glass contains silica. 2NaOH + SiO2 ↔ Na2SiO3 + H2O
(C) Aluminium reacts with excess NaOH to give Na+[Al(OH)4]-(aq) (Sodium tetrahydroxoaluminate(III)) 2Al(s) + 2NaOH(aq) + 6H2O(l) → 2Na+[Al(OH)4]-(aq) (Sodium tetrahydroxoaluminate(III)) + 3H2(g)
(D) NaHCO3 on heating gives Na2CO3 2NaHCO3 Δ→ Na2CO3 + H2O + CO2
Thus, only option C is incorrect.