Question

All of the solutions used today can be washed down the sink with water. Solid waste should be thrown in the bin. Experimental This experiment is to be carried out individually NOTE: Failure to follow the correct procedures as explained in Skill 4 will result in wildly inaccurate results. The notes below do NOT give a full description of the techniques. 0 2 Standardisation of 0.1 M sodium hydroxide with the primary standard potassium hydrogenphthalate Part A (Al) In a clean, dry 100 mL beaker take about 40 mL of the approximately 1 M solution of NaOH. Dilute the solution by a factor of ten by pipetting 25.00 mL of it into a 250 ml volumetric flask and making the volume up to 250.0 mL with deionised water. Swirl/shake/invert for about 2 minutes to mix the solution thoroughly. (A2) Transfer this solution to a 250 ml conical flask and label the solution as 0.1 NM NaOH. Retain this as your stock of 0.1 M sodium hydroxide for standardisation. (A3) Use an analytical balance in the balance room at the back of the lab to weigh out accurately about 4 g (anywhere in the range 3.9 4.1 g will do) of potassium hydrogenphthalate from the sample tubes provided into a clean, dry 100 mL beaker (see Skill 3.2). You need to know the mass accurately to t0.0002 g for your subsequent calculations. Record the exact mass in your logbook.

Answer 1

.Tu mola calan equation don t.. sua ction betweeりuntnow Acid & Sodeiur hydrorils is i Sast Aciol Molarity af standarclizod Nao solution 0.90 r1 . voluw 0,990 M x 20 m L=19.8 mmol Ao, 20 mL a) NaoH Contains 22 Lo r of dilutedl unknown acid! Contains i9.&r lol acio Hence, tN Molarity o) di호uted at unter own acid 22.boriL Fon tnail 2 rolarit 22 30 L rno lanif 0.8&7

undiluted unknosh aciol soluton iox 19 &ro 之2-6 rnL mo lanit S 76 &.87 unknown = 8.76 十8:87 +8-76 aciol 3 . Avesht San the individual cle viations 3