Question

NOTES S Br HO Br HyO Br- Br он Br Br но Br Br но Brm Formula B НBrm Formula A (color) (color) HBrm +H,O-Brm+H,O Figure 8.1. Protonation and deprotonation of HBrm. Prelab As part of your individual preparation for lab, read the experiment and answer the following questions in your lab notebook before going to lab. The copy of your answers on perforated pages from your lab notebook is due at the begin- ning of lab. Write the equilibrium expression, K, for the iron thiocyanate equilibrium system being used in this lab activity 1. The wavelength of light used in spectrophotometric measurements is cru- cial to obtaining good results; however, the wavelength is not used in the calculations. Why is the wavelength selection so important? 2. 3. Calculate the concentrations of each of the standard solutions that you will prepare using the information on pages 117-119 and in Table 8.3. Table 8.1. Concentration of Standard Solutions of FeSCN Volume of Total Volume (mL) [FESCN1 (M) Volume of 0.200 M 0.00200 M KSCN (mL) Standard Fe(NO,), (mL) 10.00 1.50 2 10.00 2.00 10.00 2.50 4 10.00 3.00

I dont need #6

Answer 1

Tecoa). & sen rood & [relsens et cog.) 2. Because at a particular wavelength, comparend is alason bed most 3. 1 Total roume (m) [Felsen et 13:56 2.609 kort 12.00 3,333x10 m. 4410tm 18.00 4.615x10rtm 12.50 Initial TF03+7m Initial Tsew.IM 441004 5410rt 1x10-3 1.5610-3 1.64103 1.54 10 3 1610-3 3410-4 4x10rq. E. 1.6x103

5. a. The Pink colour will be faded and a léged blue colour will start appearing, It's a cauilibrium, so he chate thes's prineople is established e. Teocong at will increase {eotho) ] 2t will decrease