Question

The equilibrium of Co and CF with CoCl- 5 Initial Color: blue Color after addition of HCI: Piuk bue/Paxle Color after addition of HCI: Color after heating: Pak Color after cooling: Questions Chatelier's Principle to explain the different colors found in the following equilibria. Write balance chemical equations for all chemical reactions. Write net ionic equations for the reaction between Fe(NO3)2(aq) and KSCN(aq) a Explain the color change when Fe(NO3)2 is added to the reaction at equilibrium. b Write net ionic equations for the reaction between NiCl2(aq) and NH3(aq). 2. a 2 elier's Principle Results 1. The equilibrium between Fe and SCN and Fe(SCN)2 Compare the colors in the following pairs of test tubes 1 and 3: Same ton e darker 2 and 3: 2. The equilibrium of Ni and NH3 with Ni(NHs) Color before addition of NH3 cleac Gen Color after addition of NH: bloe Color after addition of HCl: LighT Grec 3. The equilibrium involving methyl orange Rlood led (Step 4) Color after addition of dilute HCl: rauge (Step 5) Color after addition of dilute NaOH: lood Ked (Step 6) Color after addition of dilute HCl: The solubility of Ca(OH)2 4. Give the result obtained when HCl is added to a suspension of Ca(OH)2 in water. CoClzt21,O ZHCI+Colote Give the result obtained when NAOH is added. Give the identity of the substance that is formed. 1

Answer 1

1
a)
Fe(NO3)3(aq) + 3KSCN(aq) --> Fe(SCN)3(s) + 3KNO3(aq)
complete ionic equation as follows
Fe3+(aq) + 3NO3-(aq) + 3K+(aq) + 3SCN-(aq) ---> Fe(SCN)3(s) + 3K+(aq) + 3NO3-(aq)
After cancelling spectator ions we get net ionic equatio as follows
Fe3+(aq)+ 3SCN-(aq)---> Fe(SCN)3(s)

b)
color change is due to the formation of more Fe(SCN) .this is because
according to Le-Chateleir principle when reactant is added to system at equilibrium
,the system will tend to cancel that change by favoring forward reaction

2

Aq.NiCL2 exist as complex compound with water then following
reaction happens
[Ni(H2O)6]Cl2(aq) + 6NH3(aq) ---> [Ni(NH3)6]Cl2(aq) + 6H2O(l)

net ionic as follows

[Ni(H2O)6]2+(aq) + 6NH3(aq) --> [Ni(NH3)6]2+(aq) + 6H2O(l)

Thank you!