Question

are theses correct?

please correct me if they are not.

Results Fe Test Tube 2: FeSCN (aa) SCN () Fe Chemical equation: Explanation: The equilibrium shifted toward the increased the due to the addition of Fe(NO,)) because it of the Test Tube 3: FESCN 0) SCN () (as Chemical equation: Fe(ag) Explanation: Test Tube 4: Chemical equation: Fe(agk FeSCN( (aq)h Explanation: Test Tube 5: Chemical equation: Fe"( SCN () FESCN 3+ + (sq) Explanation: Test Tube 6 Chemical equation: Fe(a FeSCN(a) SCN (a) + Explanation: Test Tube 7: FESCN Chemical equation: Fe (a) (aq) (aq) + Explanation: Test Tube 8: SCN()FeSCN) Chemical equation: Fe(a) + (ag) Explanation: Test Tube 9: Chemical equation: Fe"(aq) Explanation: SCN (a)FeSCN) 34 + (aq) reaction. The reaction was determined to be an Summary: Lab 11: Le Chatelier's Principle The objective of this experiment is to observe Le Chatelier's principle by applying various stresses to a system in equilibrium PURPOSE BACKGROUND Chemical equilibrium represents a balance between a forward and reverse reaction. Changes in experimental conditions, such as increasing the concentration of a reactant, disturb the balance of the forward and reverse reactions. This causes the equilibrium to shift so that more or less of the desired product is formed The general rule used to predict the direction in which equilibrium will shift is known as Le Chatelier's principle. It states that if an external stress is applied to a system of equilibrium, the system adjusts itself to relieve the stress. Consider the following system: 3 Ha 2 NH3 Nae) + If N2 or H2 is added to the system, or if NHs is removed from the system, the equilibrium will shift to the right (produce more NHs) in response to the stress. If NH3 is added to the system, or if N2 or H2 is removed, the equilibrium will shift to the left. If the volume of the system is decreased, the equilibrium will shift to the right. Note that there are only 2 gas molecules on the right side of the equation, in contrast to 4 gas molecules on the left. When volume is decreased, the system shifts to the side of the equation with fewer gas molecules. In this experiment, you will prepare an equilibrium system for the following reaction, and study the response of this system to various stresses. Fe (a) SCN (a) FeSCN2(a) It is important in this lab to appearance, disappearance, or change of color. carefully record all observations, paying special attention to the MATERIALS Beakers, 400-mL and 250-mL 10-mL graduated eylinder Nine 15-cm test tubes 1M KSCN 1M Fe(NOs) 0.1 M AgNO 1 M NajPO4 Test tube rack Labeling tape Hot plate 0.1 M Na2C2O Solid NaF Concentrated HCI PROCEDURE 1. Add 125 mL of deionized water to a 400 mL beaker. Add 10 drops of 1 M KSCN and 10 drops of 1 M Fe(NOs)s to the water. This is your stock solution. 2. Begin heating tap water in a 250-mL beaker on a hot plate. Do not heat the water to a boil. You will use this hot water in a future step. You may share the hot water with another lab group. 3. Obtain 9 medium test tubes and label them 1-9. Add 10 mL of your stock solution to each one of the test tubes. 4. Test tube 1 will serve as a control. You will not perform experiments to the solution in test tube 1. To test tube 2, add 2 mL of 1 M Fe(NOs)s. Gently mix the solution by holding the test tube at the top and tapping at the bottom. Record your observations. 5. 6. To test tube 3, add 1 mL of1 M KSCN. Mix and record your observations. 7. To test tube 4, add 10 drops of 0.1 M AgNO3. Mix and record your observations. 8. To test tube 5, add 2 mL of concentrated HCl. Mix and record your observations. 9. To test tube 6, add 1 mL of1 M NasPO4. Mix and record your observations. 10. To test tube 7, add 1 mL of 0.1 M Na2C2O4. Mix and record your observations. 11. To test tube 8, add several crystals of solid NaF. Mix and record your observations. 12. Place test tube 9 in the beaker of previously-heated water. Record your observations. Keep all solutions until you have completed the analysis for this experiment, in case you need to refer to the color of a solution Results Fe Test Tube 2: Chemical equation: FESCN + SCN) Fe Explanation: The equilibrium shifted toward the increased the ncentratior the pdiuct due to the addition of Fe(NO;)s because it Test Tube 3:SCN Chemical equation: Fe(ag) SCN ()FeSCN The equilibrium shift towardsthe hant duu to the addihon of KSCN bucause r mutased the concuntrahon o+ the producds Explanation: Ag FeSCN Test Tube 4: Chemical equation: Fe SCN ) (aq) (ag) Explanation: The equiliunum shitttd to the left cue To the addmon of gNO3 because the toncentratibn ot reactants mcreased. aadaian of Test Tube 5: HCL Chemical equation: Fe"(ag 3t SCN) FeSCN2 + (ac) Explanation: The equcibrum shifted t the lett due th the addtn on ot HI vecause -the Concentratim of rLactonts ncreased rod PO Test Tube 6: Chemical equation: Fe + SCN (a) FeSCNa) Explanation: The auilibium emered-owards the teft due o the addrtbn of NaaPo4 because he concentiaton Of the reaclants incrased Test Tube 7: C2ai Chemical equation: Fea SCN ( FESCN2 (ag) Explanation: The equihprium shitts tovards the uft due to The addinon of NazceD4 loecause the concentration Of the reactants Increased. Test Tube 8: NaFcs Chemical equation: Fe +SCNo0 FeSCN2 (a) Explanation: The equilibnum Shifts towards the uft due t the addmo ot NaF because the concentranon ot the reactants Test Tube 9: Chemical equation: Fe Explanation: heat SCN FESCN) (aq) (aq) The eauiibrinum shifted ta the Left du torhe heat. The shift to the left produced more reactants addimon ot LKOthermic reaction. The reaction was determined to be an Summary: Questions 1. For the following situations, state whether the reaction shifts to the products, reacta briefly explain why. NH4 (a) + OH (a) heat NH3(ag) H2Ou

Answer 1

First Things first,according to Le-Chatelier's principle-

• Addition of excess reactant dives the reaction forward
• Addition of product slows down the forward reaction

Now,try to understand the following cases.In most of them (Testtubes 4 to 8) addition of an external agent results in complexation phenomenon with one of the reactants (it is
SCN
in 4 and $Fe^{3+}$ in 5 to 8) resulting in the decrease of reactant concentration,which shifts the equilibrium to LEFT.

FscN) Fe ) + SCN Cov Loa) x. Pesivete meaction comcenbration Addi tion becaus (mceane De cact ont teeactut dries additiom af frtwan ue to me 3milo neoned an the mce eactatmnloen, inesponing fuadud. antve the s backwad, iet left Comc ults complexation thereactem Addition with one S CN coa 'con) So, the procetidive back to teft (Fecsenj) to according to Le-chatelin SCN Some Hel remut m decueone Addition n Comc Fe uto Fe36 caar) tequilibriu sshifted to lett, antia att(Fe3 decteong of Conn Pprtox

als eacl AtFe" mdthe eui li bnium to make Heac 36 + PO Fe Somme come lener too left Equili brium move Hee alca, to left qilibaims shifted thhe dua to emova er uthF Fe 3A our observation during eaferiment,-4ixt°addifion hat so tbacksc wrtte mentomedom As ou diver the Meaction baclawords leactionis endothiemic and we C cm FeCsa)heat Fe Caa tene, Atpn heat u the oductside comcentation enhoncing ane