1) TABULATE Volume of pipette Burette reading(cm3)|Rough titre(cm3)|First titre(cm3)| Second titre(cm3) Final reading(cm3)|20.00|19.60|19.60 Initial reading(cm3)|0.00|0.00|0.00 Volume of acid used|20.00|19.60|19.60 Average titre=(19.60+19.60)/2 cm3 =39.20/2 cm3 =19.60cm3 Equation=>2MnO4^-+5C2O4^2-+16H^+->2NA^2++8H2O +10CO2
1bi) Conc of B in mol/dm3 CaVa/CbVb=Na/Nb (0.05*19.6)/(Cb*25.0)=5/2 5*Cb*25=2*0.05*19.6 Cb=(2*0.05*19.6)/(5*25)=1.96 Cb=0.0157mol/dm3 Cb=0.016mol/dm3
1bii) Conc in B in g/dm3 =0.0157*158 =2.4806g/dm3 =2.481g/dm3
3a) i)Simple distillation-wide boiling point difference between constituent liquid ii)Chromatography-Relative migration of constituents of mixture over an absorbent or rf-value difference of constituents of mixture
iii)Fractional distillation-Close boiling point between constituent liquid
3b) i)For easy identification of the end point ie the point of complete titration where the colour change is observed
ii)For accurate titre value ie to minimize the error margin
3c) C1=2.5mol/dm3, V1=?,C2=0.20mol/dm3,V2=500cm3 C1V1=C2V2 V1=C2V2/C1 V1=(0.20*500)/2.5 V1=100/2.5 V1=40cm3
No comments:
Post a Comment