Question

2 why is it important to keep the NAOH solution covered at all times? 0 How will the molarity of the NaOH solution be affected by its continued exposure to the atmosphere? 3. The pale pink color of the titration solution at the end point will fade to colorless after several minutes when exposed to the atmosphere. Account for this color change 4. What volume (in mL) of 0.0293 M Ba(OH)2 is required to neutralize 25.00 mL of 0.200 M HNO,? speriment #8 - Report Page 3 of

Answer 1

Answel! zla) why is it important to keep the Nach solution covered at all times Because concentrated Solutions of Naot give out fomes which are dangerous. Also Naot will react with atmospheric Col and form Na 2003. b) How will the molarity of the Nach Solution be affec- by the continued Exposure to the atmosphere? ted Here, Holarity will decrease because Naolt is hygroscopic and will absorb moisture. Also its reaction with cor will also decrease the molarity (3) Here, son thalein is pink in basic solution (high pH) in acidic solution (low pH) and colorless When the solution is Enposed to atmosphere, (02 from air dissolves in the solution ,

Forming H₂CO3 that releases Htions. =) PH is lowered =) phenolphthale in turns Colorless (4) What lolume of 0.0293 M Balolt), is required to heutralize 25.00 mL of 0.200 M HNO3? let, BaloH)2 + 2HNO3 Ba|NO3)2 + 2H₂O Holes of HNO3 = lloche concentration of HNO3 = 25 *0.200 Todo = 0.005 mol Holes of Ba(OH)2 = 1/2 * moles of HNO3 - *0.005 = 000 25 mol نیل volume of Balott) 2 = moles / Concentration of Balott). = 0.0025 0.0293 - 0085322 rolume of Buloh)2 = 85.32My orl 8513 mL