Question

2. For reaction "UCTIONS are increased by the same amount. Fe3+ (aq) + SCN (aq) $ FeSCN2(aq) (Light yeyow (.colorless) (Colorless) (red Orange Compared with Test Tube , predict the color change (darker or lighter) for Test Tubes 2-8, respectively.

My question is #2 for the reaction Fe3+ (aq) + SCN- (aq) $\rightleftharpoons$ FeSCN2+ (aq). The goal is to predict the color change (darker or lighter) for test tubes 2-8. I have attached the supplemental sheets given to help with the problem. The test tubes 2-8 are being manipulated either by temperature or things being added which can be seen by one of the pictures.

Answer 1

For the reaction

Fet +SCN) = FeSCN2+

Fes0 reSCN20 caa) caa) + SCH Оната nu m оне ന ല ന Light Red yellow . orange 2. Add to dotops of 0.1(M) Fed3 The color of the reaction System would get darkerie. color will be more at red orange .. Addition of feels means, it will get dissolved in water to produce - I Feels cage Felo + 3 cl coa) Now, the Fe3@gons increases the concentration of reactants in the system. So, accon Le- Chateliers principle, Reaction moves to sight. In short, you are adding reactants which makes the reaction to go to footwoved dissection (procket side). Hence, the colost would be med- orange ( te CA 10 (darker) ge 3. Add several crys Colom would get darker. Nitysca & Nity + Scho => addition of reactams Roth goes forward.

4. Add 20 drops of ol(M) (arty),C204 - Colon would get lighter (orta), C304 cances en Bretagent cao.com) Thé Cao.z@reacts withi Pese to give me Fe3® +362090 > [fecc904)] 200 a stable complex This means, reactant is being removed from the (Fe 30) , o system via complen formation. Hence, reaction goes to the reactant side and color becomes lighter Fe a . coast 5. Add 20 dsobs of ol (M) KF : KF coca) ? K4 fecerunt fe alma) — Pepscogs Hence, color would get lighter. Amount of reactant decreasen, hence reaction equilibrium shifts to left (reactant side to give light yellow color 6. Add 20 drops of 5 (m) NaOH): coor would get lighter Nagy hoa +Fe3 Fe (OH)3 c, d + Nah Concentration of Fe38 gets lower, so ealbh shifts to left. n стил

SO 7. Heat ima heating blocka The reaction reset Scavo a Fe scar2 @o is an enothermic reaction, die. Fe3® + scue = Fescara@ + heat. So, heating the reaction meams, increase in temp. le. we cute supplying more produt: So, the reaction shift to Left on reactant side and color would get lighter 8. Cool in an ice bath: Color would get donker. Explanation is exactly opposite to the above. ed