What initially forms as pale blue and pale green precipitate when nh3 is added to cuh2o6?

Light blue colored precipitate of copper hydroxide, [Cu(OH)₂(H₂O)₄]

Explanation:

In an aqueous solution, copper (II) exists as hexaaquacopper(II) ion, having the molecular formula [Cu(H₂O)₆]²⁺.

When ammonia (NH₃) is reacted with hexaaquacopper(II) ion, [Cu(H₂O)₆]²⁺, a light blue colored precipitate of copper hydroxide, [Cu(OH)₂(H₂O)₄] is formed, which is soluble in excess ammonia.

Reaction: [Cu(H₂O)₆]²⁺ (aq) + 2NH₃(aq) → [Cu(OH)₂(H₂O)₄](s) (↓) + 2NH₄⁺(aq)

1. they vary with a higher number because boiling is way hotter than melting