Contents es Experiments Know your Science Laboratory on. ing th i Studying the Properties of acids and bases (HCl and NaOH) by their reaction with: (a) Litmus solution (Blue/Red) (b) Zine metal (c) Solid sodium carbonate. 2, CHEMICAL REACTIONS .. wh {\4" Experiment 2. Performing and observing the following reactions and classifying them into: (a) Combination reaction (6) Decomposition reaction (c) Displacement reaction (d) Double displacement reaction (i) Action of water on quick lime (ii) Action of heat on ferrous sulphate erystals (#) Iron nails kept in copper sulphate solution (iv) Reaction between sodium sulphate and barium chloride solutions 3, ACTION OF METALS ON SALT SOLUTIONS .. awe A (ov Experiment 3. Observing the action of Zn, Fe, Cu and Al metals on the following salt solutions: (a) ZnSO, (aq) (6) FeSO, (aq) (¢) CuSO, (aq) (a) AL,(SO,), (aa) Arranging Zn, Fe, Cu and Al (metals) in the decreasing order of reactivity based on the above resultIs AMIE ovo EXPERIMENT-1 Ce gh oe evn snp sn eps net (Din erlrcgad ont 7 Mn8 DE versie inet Ce ane oS res Cues Cairne oe leeapRieeereprir gimccaesaey ae Cmusem aes | MATERIALS REQUIRED Six teat tubes, test tube stand, pH paper, glass rd, dl, HC, dl, NaOH, dil. CH,COOH, lemon juice, water, A sodium bicarbonate solition (sodium hydrogen earbonats solution) Litmussolution blue and red) zine granules, sodium carbonate, et tubes, test tube holder, fat bottomed ‘ask, lime water, distilled water, beaker. THEORY ‘Acids are thote substances which give H* ions or H,O* in aqueous solution Bases are those substances ‘hich give OH" ions in aqueous solution Beene ‘The acide or basic nature of enlition depends upon the snout of ions of OF ons present in aqueous salto. {an be determined wit the help of pH of elution The pH scale ‘ThepH of solutionis defined mathematically, asthenegative gy 23 45678 pwn aE logarithm of hydrogen ion concentration, pH =—log[H*] or pH =~ log (H,0") If pH =, solution is neutral because (H*] = [OH] If pH <7, the solution is acic because (H"]> [OH] If pH > 7, the elution is basic beeause (OH']>(H'.——le——m 1. Acids are thote subttances which are sour in taste. They Fests ‘urn blue litmus red, 2 Acids react with metals like Zn to liberate H, gas Zale) + 2HCI(dlil) —> ZnCl (ag) + Hy (@) 4. Acids react with sodium carbonate to give carbon dioxide which is colourless, odouriess and turns lime water milky 1NajC0,(s) + 2HCI (ail) — 2NaC(ag) + 1,01) eo nd NaOH) by their reaction with: Su tate Ca(OH)y(ag) + CO,(g) —y CaCO,(6) + H,00) Time waar (wtp {AB MANUAL SCIENCE | §ar biter in taste. Tey tur red itmusbive hi = . n(s) + 2NaOH (dil) + NayZn0, (aq) * be CEDURE 1. Take clean test tube ina test tbe stand 2. Take solution of aia hydrochloric acid in it 4 Pat one orto drop of hydroelrie cid onthe pH poPeT Shing enn gas ro as chown in Fig 12 4 Note the pt by comparing the clour appeared on PH pape Mh thee on elurehart Fig. 1.1 and write the colo Hin observation table 5 Take clan et tube and add NaOH solution 6: Add two drops of NaOH colton on pH paper wth che lh of ano 7. Observe the change in col {8 Write the colour change and pin te ober 9. Take another clean test tube and add eth 10, Add two drops of acetic ai eaation on pH paper servation able 11. Takes lente tae and ad lemon juin nit Take one or two drops of emon ule and ptt, paper with the help of gas ro. 12, Obwerve the colour change and record pHi the ebservation table 13. Takes lean tat ube and add water into't, Putwo drop of water on pH paper with the help fa fast rod. 14. Observe the change enlour and write pHin bervaton table, 15, Tae sean tat ube and add sodum bicarbonate slation in it, Add two drop ofthis soln pil paper with th elp of lean las rd 16, Observe the change in colour and rezrd pH in observation table. 11 Dosis natre of autions ofeach ample, acid basc or neutral with the help of pH. 35 ee Cite bead pod of moti nto bere he hag 19, Take Lmlof Hin test ube 2nd pat few dropsof red itmas olution into it, Observe the change in eaour and write in hervation able 20 Take 1m of NaOH in atest tube 8 and pt few drops of ve litmus slain nt it Observe the change in colour and record inbservation abl. 2, Tae 1 of NO in a abe ad pa fw rp od limos solution into it Observe the change in olur and wi inobseraion able eon ae 22 Take a btng tubo and ad some paces of Zn metal not Aad i Ht Psapp ith eon te meat the tube, Warm the tbe a itl, Bring a burning matehstick ear the mouth of the fire et as shown n Fig. 1.3 Write your hervation and inference in cbservation table, and compare it with slow chart, ration table ani ci (acetic acid. and aber the colour change and recrd pig rs Fg 13 Aten Hen Zn mt 6 | Wemanuascencex =AN ke few pieces of Zn metal in a boing tube, Add sufiient amount of NaOH solution, Pace stopper with ine et on the mouth ofthe boiling tube ag shown in Fig. 14. Warm a litle. Bring the matchstick near the mouth ofthejet and write «servations in observation table and draw inferences ‘Take small amount (1g) of sodium carbonate in a lat bottom Aask and add dil. HCI with the help of thistle funnel a shown in Fig. 1.5. Pass the gas through ime water and write servation and inference in observation table, ‘Take small amount (1) of sodium enrbonate in fat bottom flask. Add NaOH solution tot with the help of thistle funnel as shown in Fig. 1.6. Pass the gns through lime water and write observation and inference in abservaton table Her Fig. ActonotHClon Nico, Fig. Aeon of NaOH on NCO, OBSERVATION TABLE SNe Sample. Colour produced pH Taference 1. [DIAL 2, |DiLNeoH 3. |piLcH,coon 4 | Leman juice 5. | Water | Sodium bicarbonate salution AB MANUAL Sc!‘Experiment Colour Observation Inference ‘dd fer drops of bue Hine elton [Blue Hapa eeome ed. | HICK ina int tml fa HCL eS 2. | Add few drope of red litmus solution | No change in colour ‘Acids do not affes 1 int miata Hct estate, 3 Ae cops ou ms ation ia No change in slo Bases do ot change te NaOH | Sloe eas > Add few drops of re itmus solution in| Red tus changes to blue in| Bases turn red itmus big | lainsoa tine aes 5A HCe ictal non |The gs aed Bar wth | Zn mle wi tah warm ails wing bingo ed | ice byes |__| matt ar bas wh pn | & |Add S08 tsinemtinatsng The gen eoved ug fe Zine reacts with NaOH | Ube Warm a itl and bring a burning | producing pop’ sound iberates Hy gas |__| matchstick ner the jet. 7 |Add. HCl ein 5 advareas_ ga] Sadi carbonate The Pasthe garth erate evolved which torned lime | CO, with Hl which a eater mit rater milky. Add ail, NaOH to sodium carbonate No goa was evolved and Hime | Sodium carbonate dows atm Pass the gs throvgh ime wate. | water di not become milky. | with NaOH. _Rpsuir |. PH of dl, Cis. 2, pH of dil. NaOH i 3, pH of dil. CH,COOHTis 4, pH of emon juice i 5. pH of water is E 6. BH of NaHCO i enn its sation is — 7. HC! tums blue litmus rd, liberates H, with Zn metal and liberates CO, with NaC, 8, NaOH turns red litmus blue, borates, with Za metal on heating but does not react with sods carbonate _prtcautions BI _ D> Etat fresh juice from lemon ina clean test tube, “2. Glass rod used for one sample should be used for other sample only after washing it with water, ‘B. Do not touch or taste any ofthe solution, ‘4. Universal indieator ean be used ifpH papers are not available. _§ Use separate pH paper for testing diferent slutions. 6, Use the dilute solution of lemon juice. 17. Match the colour developed on pH paper with the pH chart careflly, §, Take small amount of Zn and HCI, otherwise large amount of H, wil be formed which may es explosion, 9, Hy should be burnt carefully through a jet 10, The apparatus must be airtight in reaction of Zn with HCl, Zn with NaOH and Na,CO, with HO M1, Do not touch or taste NaOH, HCI and Na,C0y, LAB MANUAL SCIENCEXDo not touch the 4 18, Dip the lower endothe tht anne in slutins faci or base otherwise the gs wil escape through 14. Clean zine metal with sand paper so as to remove its oxide ayer otherwise it wll react very slowly. PH of Some Common Substances and Nature of Substances aa es 4 f sateimans | on | Nunreet [sno] sameoranbaance | ott | Sears Oe Ls Tomato juice 42 2 Lime water Ca(OH), Spe aESET aris [tine wat cxon 1 [st ink 0 [ase “Milk of magmesia aeerea er Ma(OH), (eo 30. | Addie a I js [ie 2 : ZI 12 [Lamon nen aac : 13, | Gastrie juice 12 | Acidic : 14, 0.1 M HCI 1.0 | Acidic Le lice oh [i 10 [Ne a Bake 18 [sein | Univeral nator a Saation LIL ia pH [Colour Pack ot i ag | Rad | how | a ps} Ceangoeet ne, =" ts | —— 0 = es ne 70-7. Greenish-yellow tee 35 ie —— 100 Violet NEN Ql. What are acids? Give examples. ‘Ans, Acids are those substances which give H* ions in aqueous slution, 4H, 80, HCl, HNO, ee (Q2, What isthe taste of acids? ‘Ans. They ae sour in taste (Qo, Which acid is present in lemon? ‘Ans. Citi aed (Q4. What are bases? Gve examples ‘Ans, Bases ar thoeerbetanoet which gve OH- ions in aqueous slation, THEORY ‘Quick time (CaO) reacts with water to form lake lime Ca(OH C20 (8) + 1,0.) —+ Ca1OH), (ag) + beat alsin Calcium ide Iydenide is combination reaction, Ferrous sulphate, on heating, gives ferric oxide, sulphur dasde and sulphur trioxide. 2F280,0) M4 FeOyn) + 80446) + S0j6) Jen phate Ferricosie " Suphur Sulphur eh owe ose ite tis decomposition reaction ‘When iron nals are placed in blue coloured capper sulphate scltion, iron displaces copper from Cus to form FeSO, and reddish brown copper metal gets deposited. Fe() + Cu80, (ag) —> FeSO, (ag) + Cute) ion Copper sulphate Tron tt Copper sulphate Its deplacement reaction, ‘When sodium sulphate eolaton is mixed with berium chloride salton, whit precipitate of BaSO, is formed, BaCl, (ag) + Na,80, (ag) —> BaSO, (8) + 2NaCl (ag) rium Sedum chloride sulphate tis double displacement reaction, Barium Sobiom sulphate eheride 20 | LAB MANUAL SCIENCE XTERIALS REQUIRED Quick lime, water, beaker, FeSO,, hard glas tube, iron nails, CuSO, (ag), sodium sulphate solution and Sram cle tion, tat aes, mrs rons teeta DURE lb wifi patellar 3. Observe what happens, Touch the container Classify the reaction, soy ee SO = 0 Pa.24 5, Take 2g of FeSO, in a hard glass tube. 6, Hold the hard glass tube in test tube holder. 7. Heat the hard glass tube and observe the odour of gases evolved and colour of residue 8, Classify the reaction 9, Take copper sulphate solution in a beaker. 10, Put iron nals in the beaker, 11, Leave it undisturbed for half an hour. 12, Observe the change in colour of solution and metal deposited on iron nails and classify the reaction, 18, Take sodium sulphate solution in atest tube 14, Add barium chloride solution into it. 15, Observe what happens and record the observation. 16. Classify the typeof reaction. ;SERVATION TABLE iron CaO +H,0—> Ca(OH, container and ada water slowly Ws combination reaction. | 2 [Heat ferovs sulphate slid ina Topas withulfstingsmel| 9750, —!-» Fe,0, +80, +80, | har laste. © produced and residue is] 1 i etompoon rention, | reddish brown, 7, | Take CuS0, faq) in a beaker and| The colour of salaton changes | Fe) ¥ CaSO, aa) —> PSO, (aa) sd few iron malin topalegreen and reds bes + Cu topper metals deposit. | ti displacement reaction m TAB MANUAL SCIENCEX | 24a ae 4, | Take sodium sulphate solution in a | White precipitate is formed. | Na,SO, (aq) + BaCl, (ag). test tube and add barium chloride BaSO, (6) + solution into it. It is double displacement _”ESULT Reaction of CaO with H,O is a combination reaction, heating of FeSO, is a decomposition reaction, of iron nails with CuSO, (ag) is a displacement reaction, reaction of sodium sulphate (aq) with chloride (ag) is a double decomposition reaction. _ARECAUTIONS 1. Do not touch iron container for long time in the reaction of CaO with H,0. 2. Do not touch test tube while heating FeSO, 3. Do not touch or taste copper sulphate solution. 4. Do not touch or taste barium chloride solution.3. ACTION OF METALS ON SALT SOLUTIONS ool proeamenn.s Ml COtervng th ation of Za, Fe, Cu and Al metals on the flowing salt solutions: {a) 2180, (99) (©) FeS0, (aq) {6 C280, (a9) (@ A480), 9) Arranging Zn, Fe Cu and Al (metals inthe decreasing order of reactivity based onthe above result {THEORY More reactive metas can displace less reactive metals fom ther salt solutions, These reactions are called tispleement reactions, ‘Alcan displace Zn, Fo, and (Cu from their salt solution, therefor, itis most reactive among Zn, Fe, Cu 2A) + 828009) —y ALSO, faq) +8209) 2Al() + FSO (aq) —+ AlfS0) (oq) + Fe 2AN(6) + 3CuS0 (ag) —+ AL(80,)(aq) + 8Cu(s) ‘ncan displace Fe and Cu rom tr slslution, there, nis mare reactive than Fe and Ci nls) + CuSOJo0) + 2580/00) + Cus) al) + FeSO, (a) —+ 2580, (00) + Fl) Fecan dspace copper fom copper sulphate soliton, therefor, is more reactive than coppe. Fel) + CuSOag) + FeSO,a) + Cul) Coppers least reactive among Fe, Za, Cu and Al FERIALS REQUIRED Akminium ol, copper turnings, ine granules, iron lings, FeSO, solution, copper sulphate sltion, zine talpete soliton, alumni sulphate pluton et tubes YCEDURE 1. Take fou test tubes and ad 2280 (a), Fe80 (a0, CuSO, (0) Al{0 (a) 2. Adda pie of luminium fl in all of hem, 2. Obeerve the changes and recrd the cbeervatios in observation table 4 Take 280 a), FeSO, aq), CuS0,(aa) and Al,(80,) a in four tat tubes agin, Aad sine metal in all of them 5 6. Observe the changes and record the observations 1 Take Zn$0,(0g), FeSO (ag), CuSO faq) and Al($0,), (ag) in four test tubes. 8. Add iron fings inal f them TAB MANUAL SCIENCE:X | 29Ne mn am ‘Observe the changes and write in observation table. a 10. Take Zn80 (ag), FeSO (aq), CuSO, (a9) and Al,(S0,)4(09) in four test tubes again, 11. Ada copper turnings in al of them, 12, Observe the changes in colour and metal deposited and write in observation table, OBSERVATION TABLE The mtn bese eros od revah Za metal gt depsite. 2 | Ret Amat n PSO, alate elation bse lures and ‘ereyish-black iron metal got deposited. 3 [Allstate Ga, an |Theslution bce clues and reddish-brown copper metal got poet [Ai Atta A509 tn | No action | Aled Za metal Za$0, nation. [Noein ok ae © | Rides etl in FSO, oad Te ation boane os wd rvs lack Fo met tepid 7. [Astin 60, ston, The lation Dame colourless and conver metal (rdehSrom) got peed [Added Ge wetal in aluntalam | Neen tk Hane slate ean, 3) Ade io tal FSO) | Novation ok lc Tron dies wat Fay Fo, 10 | Added meialin a0 fe) | No eto a es rns ea 11. [Aditi tla C3800) | Renown capper viel wt [tn fb moe eg nd extn ame | cpp pom 12. [Added rom meta in amu | No est ak pase roses eas cpa sltion 1B] Ae ep metalin C50 ato | Noein oka cu80, 1 ile pp alin FSO, slat | No eso ak Copper es ra 15 | Aldo epper tain 80, si, [Ro ection a Hac a= ta 16, [ded copper metal In AiO), | Novecon von Bored Capper Ten aa clin. Al RESULT The order of reactivity of metal is Al > Zn > Fe > Cu. 30 | LAB MANUAL SCIENCEX© Clean the metals with sand paper. 2. Some may react slowly, therefore, observe the changes carefully. 3. Do not touch or taste the chemicals. 4, Wash your hands with soap, if you touch any solution.