Join Examfocus on Facebook For Hot Updates Click Here

VERIFIED CHEMISTRY ANSWER
1) Tabulate Burette reading|Final burette reading(cm^3)|Initial burette reading (cm^3)| Volume of acid used(cm^3)| Rough- 24.10,0.00,24.10 First- 23.80, 0.00, 23.80 Second- 23.75, 0.00, 23.70 Third- 23.75, 0.00, 23.75 Average volume of A used = 23.80 + 23.70 + 23.75cm^3/3 =23.75cm^3 1bi) CAVA/CcVc=2/1 Cc=CAVA/2VC =0.100*23.75Moldm^-3/2*25.00 =0.0475moldm^-3 amount of A used = 0.100x VA/1000=0.100*23.75/1000 =0.00237 2moles Of A = 1mole of C 0.002375mol of A = 0.002375mol/2 100cm^3 of C contain 0.00237*100mol/2*25 =0 1000cm3ofCcontained0.002375x1000mo 2×25 =0.0475mol concentration of C in moldm-3 =0.0475moldm-3 1bii) Molar mass of Bing mol-1: Molar mass of Na2CO3.yH2O=mass concentration of Bingdm-3 molar concentration of Binmoldm-3 =13.6gdm-3 0.0475moldm-3 =286gmol-1 1biii) Molar mass of Na2CO3 = [(2×23)+12+(16×3)]=106gmol-1 Mass of anhydrous Na2CO3=106×0.0475gdm-3 =5.035gdm-3 Mass of water=13.6-5.035gdm-3 =8.565gdm-3 Mass of Na2CO3 =Molar mass of Na2CO3 Mass of water y×Molar mass of water 5.035=106 8.565 18y y =106×8.565 5.035×18 =10 2) Tabulate Test (a)(i)Fn+H2O,then filter Observation White residue and blue filtrate was observed Inference Fn is a mixture of soluble and insoluble salts Test (ii)Filtrate+NaOH(aq)in drops,then in excess Observation A blue gelatinous precipitate which is insoluble in excess NaOH(aq)was formed Inference Cu2+present Test (iii)Filtrate+NH3(aq)in drops,then in excess Observation A pale blue gelatinous precipitate was formed. The precipitate dissolves or is soluble in excess NH3(aq)to give a deep blue solution Inference Cu2+confirmed Test (iv)Filtrate+dil.HNO3 +AgNO3(aq) Observation No visible reaction White precipitate formed Inference Cl-present Test +NH3(aq)in excess Observation Precipitate dissolved in excess NH3(aq) Inference Cl-confirmed 2a) Tabulate Test (i)Fn+H2O,then filter Observation White residue and blue filtrate was observed Inference Fn is a mixture of soluble and insoluble salts Test (ii)Filtrate+NaOH(aq)in drops,then in excess Observation A blue gelatinous precipitate which is insoluble in excess NaOH(aq)was formed Inference Cu2+present Test (iii)Filtrate+NH3(aq)in drops,then in excess Observation A pale blue gelatinous precipitate was formed. The precipitate dissolves or is soluble in excess NH3(aq)to give a deep blue solution Inference Cu2+confirmed Test (iv)Filtrate+dil.HNO3 +AgNO3(aq) Observation No visible reaction White precipitate formed Inference Cl-present Test +NH3(aq)in excess Observation Precipitatedissolvedin excessNH3(aq) Inference Cl-confirmed Test 2bi)Firstportionof residue+NaOH(aq)in drops,then in excess Observation White powdery precipitate which is insoluble in excess NaOH(aq) Inference Ca2+ present Test 2bii)Second portion of residue+dil.HCl Observation Effervescence/bubbles; colourless,odourless gas evolved. Gas turns lime water milky and turns damp blue litmus paper red. Inference Gas is CO2 CO3^2- or HCO3 -present 3i) lime juice is acidic in nature and the colour of methyl orange in acidic medium is red 3ii) Iron(iii)chloride will be reduced to iro(ii) with yellow deposit of sulphur 3iii) The color of KM2O4 is decolorized because SO2(g) acts as a reducing agent. 3iv) Addition of ethanoic acid to KCO3 results to the liberation of a colorless and odorless gas CO2 which turns lime water milky =============== (3) (i ) P is delivery tube Q is drying tower R is quick lime S is dry ammonia T is retort stand (ii)By upward delivery (iii)It serves as a drying agent (iv)Ca(OH)2(s)+2NH4(s)- >CaCl2+2H2O(l)+2NH3(g)a 3c. Sulfur dioxide gas (SO2) is bubbled through a solution of acidified potassium permanganate (KMnO4). An oxidation-reduction reaction occurs. Potassium permanganate has a purple colour. Sulphur dioxide is a reducing agent. Potassium permanganate is an oxidizing agent. When sulphur dioxide reacts with potassium permanganate the solution decolourizes. Color changes from Purple to colorless 3i)Lime Juice is acidic in Nature and the colour of methyl orange in acidic medium is red. =====KEEP REFRESHING===
ANSWERS LOADING 99% KEEP ON REFRESHING THIS PAGE
Thank's for reading my article CHEMISTRY PRACTICALS ANSWERS AVALIABLE
Created at 2017-04-11 13:25:15


Share: