Question

please answer all question show work number 7 only please

The pH of 2.0M HCI is a) 2.0, b) 1.0, c) 0.0, d)<0.0. 1. 2. Thymol blue appears red below pH 1.0, yellow between pH 2.5-8.0, and blue above pH 9.5. An aqueous solution turns green upon adding one drop of thymol blue. The pH of this solution is a) 0.5, b) 7, c) 9, d) 11. The buffer HF/F can' be prepared by mixing a) HF and NaF, b) HCl and NaF, c) HF and NaOH, d) all of 3. the above. The effective pH range of the KF/HF (K-6.8x10) buffer is a) 2.2 - 4.2 b) 1.2-4.2, c) 2.2-5.2, d) all possible. 4. 5. Which cannot work as ligand for metal complexes? a) Hs0, b) H2O, c) OH, d) 0 Number of geometric isomers of square planar Pt(NHs)2Cl2 complex is a) 0, b) 2, c) 3, d) 4 6. 7. An aqueous solution is 0.00500 M in Ca(OH)2. Give [OH], [H'], pH, and pOH

Answer 1

I d. The pH of 2.2M He is Here [H - B2M [since strong reid ] Hence pH e – logo (2.0) - - 0.301 <0.0 (2) Thymol blue appears red below 1.o, yellow between PH 2.5-80, 2. blue above 9.5. Depending Hence it was appears green in the pH range 9. Lon the Ans: (C) 1 wavelength of light ? 3. Buffer Hf/f can be prepared by mixing as HF & NaF Ans: (a) 4. For buffer solutions effective pH range is pka 11. Hence given Ka-6.8810 The pka a- log (6.8 x 204 ) 3.167 ~ 3.2.

Hence effective pt range is 3.24-1 to 3.2+1 je. 2.2 to 4.2. Ans: (a) 5. (a) Hot cannot work as a ligand for metal complex as it has no asided lone - pairs of electrons & novac arbital to accept electron cloud. Ausicas 6. Number of geometric isomers of square plannar Pt (NH3) Cl2 is (6) 2 Ans (6) N a ang NH3 AN -a HAN ciso trans- 7. Concentration of Ca(OH), in aqueous solution 0.00500 (M) less It is to Astaringly soluble in water but is a strong base. Hence we can assume it completely dissociates after dissolving Concentration is low, so lets assume it dissolves Completely too. Hence. Concentration of OH & [ou]. 20.00500 x 2 (M) Ca (OH) Ź Ca 2+ cap) +2014 (aq) 20.01(M) So 1 mol of caCoH) (dissolved) gives 2 mobs of OH" so poH a-log [ort] - log (0.01) 2. Lost ] = 0.0L for water ionic product [HT] [OH I LO" At this high concentration of lon lets say, water dissoci rates to give 6 x (Mille ut & c x (M) ot. Hence x. (x+0.04) 10" 0.01.x + x² 0.01 x 10 x a Lola a 10-12 [neglecting small -14 -14 value of x²] 0.01

12 Hence . [4+1 = 10' Hence pH. – log Cut en boy (2002) -12. [41] = 102 Tour] •ool PH 12 polt 22. Hence