In the reaction of copper and silver nitrate, a new substance appeared in the test tube. describe the physical appearance of the substance and identify its chemical formula.

The new substance which has appeared in the test tube is silver (Ag).  

Solid silver that emerges from copper as a precipitate.

Explanation:

This is the reaction

Cu (s)  +  2AgNO₃ (aq) →  Cu(NO₃)₂ (aq)  +  2Ag (s) ↓

It is a redox type

(Cu → Cu²⁺  +  2e⁻) .1  OXIDATION

(Ag⁺  + 1e⁻  →  Ag) .2  REDUCTION

Cu  + 2Ag⁺  + 2e⁻  → Cu²⁺  +  2e⁻  + 2Ag

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

2b2t

explanation:

2b2t