Tiêu đề রাসায়নিক পরিবর্তন Written-Practice-Sheet_Without-Solve.pdf ✅

ivmvqwbK cwieZ©b  Varsity Practice Sheet 1 PZz_© Aa ̈vq ivmvqwbK cwieZ©b Chemical Changes ACS Chemistry Department Gi g‡bvbxZ wjwLZ cÖkœmg~n ivmvqwbK wewμqv I wMÖb †Kwgw÷a 1| UvBUvwbqvg `ywU wfbœ wfbœ c×wZ Øviv AvKwiK †_‡K wb®‹vkb Kiv hvq| (i) AwaKZi mwμq avZzi e ̈envi : TiO2+ 2Mg  Ti + 2MgO (ii) AvKwi‡Ki Zwor we‡kølY : TiO2  Ti + O2 Kvw•ÿZ Drcv‡` wewμqK cigvYyi me©vwaK Dcw ̄’wZi aviYv e ̈envi K‡i Dc‡ii †Kvb c×wZwU wMÖbvi wbY©q Ki| [Ti = 47.88 Ges Mg = 24.3] [BUET 18-19] DËi: (ii) bs c×wZ AwaKZi wMÖbvi| 2| wMÖb †Kwgw÷a Kx? GUg BKbwg Kv‡K e‡j? 3| B-d ̈v±i Kv‡K e‡j? CH2 = CH – CH2Cl + H2O  CH2 = CH – CH2OH + HCl wewμqvq CH2 = CH – CH2OH Drcv` Ges HCl eR© ̈| wewμqvwUi ‘E’ d ̈v±i KZ? DËi: 0.63| 4| Bw_wjb A·vBW (C2H4O) Drcv`‡bi `ywU mgxKiY wb¤œiƒc : (i) C2H4 + Cl2 + Ca(OH)2  C2H4O + CaCl2 + H2O (ii) C2H4 + 1 2 O2 Ag250C –––––––– C2H4O G `ywU c×wZi g‡a ̈ †KvbwU wMÖbvi c×wZ n‡e, Zv e ̈vL ̈v Ki| mgvavb: (ii) bs c×wZ wMÖbvi| wewμqvi nvi 5| A ̈v‡gvwbqv Aw·‡R‡bi mv‡_ wb‡¤œi mgxKiY Abyhvqx wewμqv K‡i| 4NH3(g) + 5O2(g) = 4NO(g) + 6H2O(g) †Kv‡bv gyn~‡Z© A ̈v‡gvwbqv 0.24 mol L–1 s –1 nv‡i wewμqv Ki‡j wewμqvwUi nvi mgxKiYwU wjL Ges H2O(g) Drcv`‡bi nvi wbY©q Ki| [BUET 17-18] DËi: 0.36 mol L–1 s –1 6| KI Gi `ae‡Y †Kvb wbw`©ó NbgvÎvi H2O2 `aeY †hvM Ki‡j 10 †m‡K‡Û 10–5molL–1 Av‡qvwWb gy3 nq| Av‡qvwWb Drcbœ nIqvi G wewμqvwUi Mo MwZ‡eM wbY©q Ki| [KU 15-16] DËi: 10–6 molL–1 sec–1 7| wewμqvi nvi Kx? NbgvÎv e„wׇZ wewμqv nvi e„w× cvq †Kb? 8| wewμqvi nvi I nvi aaæe‡Ki g‡a ̈ wZbwU cv_©K ̈ wjL| 9| wb‡Pi wewμqvi Rb ̈ wewμqvi nv‡ii ivwkgvjv †jLÑ 5Br– (aq) + BrO– 3 (aq) + 6H+ (aq)  3Br2(aq) + 3H2O(l) 10| CCl4 Gi Dcw ̄’wZ‡Z 318K ZvcgvÎvq N2O5 Gi we‡qvRb Kiv n‡jv| wewμqvi ïiæ‡Z N2O5 Gi NbgvÎv 2.33 M Ges 184 min ci N2O5 Gi NbgvÎv cvIqv †Mj 2.08 M wewμqvwU wb¤œiƒcÑ 2N2O5(g) –– 4NO2(g) + O2(g) wewμqvwUi Mo nvi wbY©q Ki| GB mg‡q NO2 •Zwii nvi KZ wQj? DËi: 2.72  10–3mol L–1min–1 wewμqvi μg 11| M ̈vmxq Ae ̄’vq mvB‡K¬v‡cÖv‡cb †_‡K mvB‡K¬v‡cÖvwcb •Zwi GKwU cÖ_g μg wewμqv hvi nvi aaæeK 500C G 6.7  10–4 s –1 | (a) mvB‡K¬v‡cÖv‡cb Gi cÖv_wgK NbgvÎv hw` 0.25 M nq Z‡e 8.8 min ci Gi NbgvÎv KZ n‡e? (b) mvB‡K¬v‡cÖv‡cb Gi NbgvÎv 0.25 M †_‡K n«vm †c‡q 0.15 M n‡Z KZ mgq jvM‡e? [BUET 16-17] DËi: (a) 0.1755 M, (b) 762.43 s 12| cÖvPxb mf ̈Zvi GKwU Kv‡Vi cyZz‡ji †ZRw®ŒqZvi gvb 12 cpm g–1 cvIqv †Mj| cÖv_wgK Ae ̄’vq cyZzjwUi †ZRw®ŒqZvi gvb wQj 20 cpm g–1 | cÖvPxb mf ̈Zvi eqm wbY©q Ki| (†ZRw®Œq Kve©‡bi Aa©vqy 5600 eQi) [CUET 09-10, BUET 10-11] DËi: 4127.88 yr 13| 500C ZvcgvÎvq NO2 Gi we‡qvRb wewμqvi †eM aaæeK 2.4  10–3 dm3mol–1 sec–1 KZ cÖv_wgK NbgvÎvq wewμqvwUi Aa©vqyKvj 15 minutes n‡e? [BUET 08-09] DËi: 0.4629 mole dm–3 14| GKwU 1g μg wewμqvi nvi aaæeK 1.05  10–2 sec–1 | hw` wewμq‡Ki cÖviw¤¢K NbgvÎv 0.8 mol/dm3 nq, Zvn‡j 3 wgwbU c‡i nvi KZ? DËi: 1.221  10–3mol L–1 s –1 15| †iwWqv‡gi Aa©vqyKvj 1590 eQi| †iwWqv‡gi GKwU bgybv cÖviw¤¢K NbgvÎvi 10% G n«vm †c‡Z KZ mgq jvM‡e? DËi: 5282.11 year
2  Chemistry 1st Paper Chapter-4 mwμqY kw3 16| mwμqY kw3 Kx? A‡Uv cÖfveK Kv‡K e‡j? 17| †Kv‡bv wewμqvi †ÿ‡Î 338 K ZvcgvÎvq †eM aaæe‡Ki gvb 328 K ZvcgvÎvq †eM aaæe‡Ki gv‡bi wØ ̧Y n‡j wewμqvwUi mwμqY kw3i gvb MYbv Ki| DËi: 63.13 kJ mol–1 18| A + B ⇌ C + D 500 K I 530 K ZvcgvÎvq wewμqvwUi †eM aaæe‡Ki gvb h_vμ‡g 1.9510–4 L mol–1 s –1 I 1.7510–3 L mol–1 s –1 n‡j wewμqvwUi mwμqY kw3i gvb wbY©q Ki| DËi: 161.18 kJ mol–1 19| wewμqv nv‡ii Dci ZvcgvÎvi cÖfve K = Ae –Ea/RT mgxKiY Øviv cÖKvk Kiv hvq| GLv‡b K n‡jv wewμqv nvi aaæeK I Ea nj mwμqY kw3| K Gi gvb 0C ZvcgvÎvq 0.237  10–4L mol–1 s –1 I 25C ZvcgvÎvq 2.64  10–4L mol–1 s –1 n‡j mwμqY kw3 wbY©q Ki| [BUTex 19-20] DËi: 65.21558 kJ mol–1 cafveK I Gi e ̈envi 20| cÖfve‡Ki 5wU •ewkó ̈ wjL| ivmvqwbK mvg ̈ve ̄’v 21| N2(g) + 3H2(g) ⇌ 2NH3(g) ; H = – 92.38 kJ. wb‡¤œ cÖ`Ë cÖkœ ̧‡jvi DËi `vI: (a) mg‡qi mv‡_ N2 I NH3 Gi cwigv‡Yi cwieZ©b wP‡Î †`LvI| Df‡qi mv‡c‡ÿ m¤§yL wewμqvi nvi †jL| (b) wewμqvwUi mvg ̈ve ̄’vi Dci Zvc I Pv‡ci cÖfve wK n‡e? (c) mvg ̈aaæeK (K) Gi Dci cÖfve‡Ki †Kvb cÖfve i‡q‡Q Kx? [DU 19-20] 22| GKwU dv‡b©‡m 35% CO2 – 65% CO M ̈vm wgkÖY e ̈envi K‡i 700C G ÷xj‡K Zvc w`‡j Gi Dci gwiPv co‡e wKbv Zv wbY©q Ki| [†`Iqv Av‡Q; Fe(s) + CO2(g) = FeO(s) + CO(g); K = 1.43] [BUET 20-21] DËi: gwiPv co‡e bv| 23| wb‡¤œv3 ivmvqwbK wewμqvmg~‡n mvg ̈ve ̄’vi Pvc n«vm K‡i M ̈vmxq AvqZb e„w× Ki‡j wewμqvi wgkÖ‡Y Drcv‡`i †gvj msL ̈vi Kx cwieZ©b n‡e e ̈vL ̈v Ki| (i) CaO(s) + CO2(g) ⇋ CaCO3(s) (ii) 3Fe(s) + 4H2O(g) ⇋ Fe3O4(s) + 4H2(g) [BUET 20-21] 24| A2(g) + B2(g) ⇋2AB(g) wewμqvwU 2L AvqZ‡bi cv‡Î m¤úbœ Kiv nq| wewμqvi ïiæ‡Z A2 Gi †gvjmsL ̈v 2, B2 Gi †gvjmsL ̈v 2 Ges mvg ̈ve ̄’vq Drcv‡`i †gvjmsL ̈v 3.12| Kp I Kc Gi gvb wbY©q Ki| [BUTex 21-22] DËi: 50.28 25| GKwU DfgyLx ivmvqwbK wewμqvi n = 1 2 | KZ †Kjwfb ZvcgvÎvq Kp I Kc Gi gvb h_vμ‡g 40.5 Ges 5.5 n‡e? [R = 0.082 L.atm.mol–1 .K–1 ] [CKRUET 21-22] DËi: 661.26K 26| A2 + B2 ⇌ 2AB wewμqvq mvg ̈ aaæeK Kp n‡j, AB ⇌ 1 2 A2 + 1 2 B2 wewμqvi mvg ̈ aaæeK KZ? [KUET 19-20] DËi: 1 Kp 27| jv-kv‡Zwjqvi bxwZ †jL| fiwμqvi m~Î Kv‡K e‡j? 28| mvg ̈aaæeK Kc Gi gvb k~b ̈ nq bv †Kb? 29| DfgyLx wewμqv KL‡bv †kl nq bv †Kb? ev ivmvqwbK mvg ̈ve ̄’vi MwZkxjZv e ̈vL ̈v Ki| 30| DuPz RvqMvq eid ax‡i M‡j †Kb? 31| (i) A2 + 3H2 ⇌ 2AH3 + Zvc (ii) A2 + O2 ⇌ 2AO2 – Zvc (i) I (ii) wewμqvi ZvcgvÎv cwieZ©‡bi mv‡_ mvg ̈v1⁄4 Kp Gi cwieZ©b †jLwP‡Îi mvnv‡h ̈ †`LvI| 32| 500 K ZvcgvÎv I 2 atm Pv‡c N2(g) + 3H2(g) ⇌ 2NH3(g) wewμqvwUi Kp = 1  10–2 atm–2 | Zvn‡j 500 K ZvcgvÎv I 10 atm Pv‡c 2 3 NH3(g) ⇌ H2(g) + 1 3 N2(g) wewμqvwUi Kp = ? DËi: 4.641 atm 2 3 33| (i) N2(g) + 3H2(g) ⇌ 2NH3 Gi mvg ̈aaæeK K1 (ii) N2(g) + O2(g) ⇌ 2NO(g) Gi mvg ̈aaæeK K2 Ges (iii) H2(g) + 1 2 O2(g) Gi mvg ̈aaæeK K3 n‡j, 2NH3(g) + 5 2 O2(g) ⇌ 2NO(g) + 3H2O(g) Gi mvg ̈aaæeK (K) wbY©q Ki| DËi:      K2    3 3 
ivmvqwbK cwieZ©b  Varsity Practice Sheet 3 34| 3A(g) + 2B(g) ⇌ 4C(g) + D(g)-wewμqvwU‡Z A Gi we‡qvRb gvÎv 10% n‡j B Gi we‡qvRb gvÎv wbY©q Ki| †`Iqv Av‡Q, A, B C I D Gi cÖv_wgK †gvjmsL ̈v h_vμ‡g 4, 7, 0 I 1 mol| DËi: 0.038 ev 3.8% 35| 0.1 mole COCl2 A cvÎ (1 dm–3 ) A cv·K 400C ZvcgvÎvq DËß Kiv nj mvg ̈ve ̄’vq †gvU Pvc nq 8  105 Nm–2 | A cv‡Î msNwUZ we‡qvRb wewμqvq D3 †hŠ‡Mi we‡qvRb gvÎv wbY©q Ki| DËi: 42.97% 36| KwVb A ̈v‡gvwbqvg Kve©v‡gU‡K D”P Zv‡c we‡qvwRZ Ki‡j A ̈v‡gvwbqv I Kve©b WvB A·vBW M ̈vm Drcbœ nq| NH4CO2NH2(s) ⇌ 2NH3(g) + CO2(g) 25C ZvcgvÎvq G mvg ̈ wewμqvwUi aaæeK, Kp = 2.31 × 10–4 n‡j, Kc Gi gvb wbY©q Ki| DËi: 1.577 × 10–8 37| 35C ZvcgvÎvq 2.5L AvqZ‡bi k~b ̈ cv‡Îi g‡a ̈ 3.06g KwVb NH4HS wb‡q we‡qvwRZ Kiv n‡jv| mvg ̈ve ̄’vq NH4Hs Gi 30% we‡qvwRZ n‡q NH3 I H2S Drcbœ K‡i| mvg ̈aaæeK Kp I Kc Gi gvb wbY©q Ki| DËi: 0.0331 38| 25C ZvcgvÎvq wb‡¤œi wewμqvi cÖgvY gy3kw3i cwieZ©b – 45.65 kJ mol–1 N2O4(g)  2NO2(g) wewμqvi mvg ̈aaæe‡Ki gvb MYbv Ki| DËi: 1.0046 × 108 39| GKwU wewμqvi In Kp ebvg 1 T †jL wP‡Îi Xvj 21645.02K| wewμqvwUi H wbY©q Ki| DËi: – 179.95 kJmole–1 40| 25C ZvcgvÎv 2SO2(g) + O2(g) ⇋ 2SO3(g) wewμqvi Kp = 3  1024 n‡j Gi Kc Gi gvb KZ? DËi: 7.342  1025 41| 6.00 L AvqZ‡bi GKwU cv‡Î 230C ZvcgvÎvq mvg ̈ve ̄’vq 0.0222 mol PCl3, 0.0189 mol PCl5 Ges 0.1044 mol Cl2 Dcw ̄’Z _v‡K| wb‡¤œi wewμqvi Rb ̈ Kc wbY©q Ki: PCl3 + Cl2 ⇌ PCl5 DËi: 48.9 L mol–1 42| 2NO(g) + O2(g)⇋ 2NO2(g) 25C ZvcgvÎvq wewμqvwUi mvg ̈aaæe‡Ki gvb 2  1012 n‡j cÖgvY gy3 kw3i cwieZ©b MYbv Ki| mvg ̈ve ̄’vq wewμqvwU wewμqK bvwK Drcv‡`i w`‡K m‡i hv‡e? DËi: mv‡g ̈i Ae ̄’vb Drcv‡`i w`‡K m‡i hv‡e| 43| 2CH4(g) ⇋ CH3 – CH3(g) + H2(g) 25C ZvcgvÎvq cÖgvY gy3 kw3i cwieZ©b 78.7kJ mol–1 n‡j mvg ̈ aaæe‡Ki gvb MYbv Ki| DËi: 1.611  10–14 44| 60C ZvcgvÎvq N2O4 Gi we‡qvR‡b mvg ̈ aaæeK Kp = 0.664 atm| †gvU Pvc 10 atm n‡j we‡qvRb gvÎv KZ? DËi: 0.127784 45| 2SO2(g) + O2(g)⇋2SO3(g) Gi mvg ̈ wewμqvi mvg ̈ aaæeK Kp Gi gvb 4.75| mvg ̈ve ̄’vq SO2 I SO3 Gi AvswkK Pvc h_vμ‡g 0.25 atm I 0.45 atm n‡j O2 Gi AvswkK Pvc wbY©q Ki| DËi: 0.682105 atm 46| 25C ZvcgvÎvq CH3 – COOH I C2H5 – COOH Gi we‡qvRb aaæe‡Ki gvb h_vμ‡g 1.8  10–5 I 1.45  10–5 | 0.1 M NbgvÎvi C2H5 – COOH `ae‡Y CH3 – COOH `aeY †hvM Kiv n‡jv| CH3 – COOH `ae‡Yi NbgvÎv KZ n‡j C2H5 – COOH Gi we‡qvRb gvÎv AcwiewZ©Z _vK‡e? DËi: 8.056  10–2 M. 47| N2 + 2H2 ⇌ 2NH3; wewμqvwUi kp wbY©q Ki| DËi: 4 2 (a + 3b –2) 2 27 (a – ) (b – )P 2 48| 500 K ZvcgvÎvq 20 L wewμqv cv‡Î 1.57 mol N2, 1.92 mol H2 Ges 8.13 mol NH3 wgwkÖZ Kiv nj| H ZvcgvÎvq N2(g) + 3H2(g) ⇌ 2NH3(g) Gi Rvbv Kc Gi gvb 1.7 × 102 n‡j eZ©gv‡b wgwkÖZ M ̈vm mnKv‡i wewμqvwU †Kvb w`‡K AMÖmi n‡e? DËi: wewμqvwU evg w`‡K AMÖmi n‡e 49| N2O4 ⇌ 2NO2 wewμqvi Rb ̈ 298 K ZvcgvÎvq I 100 kPa Pv‡c bvB‡Uav‡Rb †UUavA·vBW 20% we‡qvwRZ nq| D3 we‡qvR‡bi Rb ̈ Kp wbY©q Ki| DËi: 16.67 atm 50| N2O4 ⇌ 2NO4 wewμqvi Rb ̈ 45C ZvcgvÎvq N2O4 Gi we‡qvR‡bi mvg ̈aaæeK Kp = 67.28 kPa| mvgwMÖK Pvc 1013.25 kPa n‡j we‡qvRb gvÎv KZ n‡e? DËi: 67.28 4120.28 51| N2 + 3H2 ⇌ 2NH3; 2 L AvqZ‡bi mvg ̈wgkÖY‡K cÖkwgZ Ki‡Z 1000 ml 1 M HCl cÖ‡qvRb n‡j mvg ̈aaæeK Kc = ? DËi: 8 27
4  Chemistry 1st Paper Chapter-4 52| A + B ⇌ C + D GLv‡b A = 3 mole, B = 2 mole, C = 1 mole, D = 7 mole; Kc = 0.8 I D Gi we‡qvRbgvÎv 0.1 n‡j mvg ̈ve ̄’vq A Gi †gvj msL ̈v KZ? DËi: 3.7 Mole. A¤ø-ÿviK mvg ̈ve ̄’v 53| (a) cvwbi we‡qvR‡bi †ÿ‡Î ̄^-we‡qvRb aaæeK (Kd) Ges AvqwbK- ̧Ydj (Kw) Gi ivwkgvjv †jL| (b) Kw Gi Ici ZvcgvÎvi cÖfve Kx? [DU 21-22] 54| B_vbwqK Gwm‡Wi Rjxq `ae‡Yi we‡qvRb mvg ̈ve ̄’v †`LvI Ges Gi Ka msÁvwqZ Ki| †Kvb k‡Z©, pKa = pH n‡e, cÖ‡qvRbxq mgxKiYmn e ̈vL ̈v Ki| [DU 20-21] DËi: pKa 55| nvB‡Wav‡Rb Avq‡bi 5.6  10–2 M NbgvÎv wewkó 500 mL Av‡gi i‡mi mv‡_ nvB‡Wav‡Rb Avq‡bi 4.4  10–2 M NbgvÎv wewkó 500 mL Kgjv †jeyi im wgwkÖZ K‡i d‡ji i‡mi GKwU wgkÖY •Zwi Kiv nj| d‡ji i‡mi wgkÖ‡Yi pH KZ n‡e? d‡ji i‡mi wgkÖYwU cvb‡hvM ̈ n‡e Kx? [BUET 16-17] DËi: pH = 1.301, cvb‡hvM ̈ n‡e bv| 56| 0.01 M NH4OH (Kb = 1.8  10–5 ) `ae‡Yi pH MYbv Ki| [BUET 10-11] DËi: 10.6276 57| 200 mL 0.1 M H2S `ae‡Y cvwb †hvM K‡i NbgvÎv KZ Ki‡j H2S Gi we‡qvRb 10 ̧Y e„w× cv‡e? [H2S Gi Ka = 9.1  10–8 ] [BUTEX 20-21] DËi: 2.55  10–3 M 58| 10 mL 1 M HCl G cvwb †hvM K‡i 100 mL AvqZ‡b cwiYZ Kiv n‡j †m `ae‡Yi pH KZ? [RU 19-20] DËi: 1 59| pH ej‡Z Kx eyS? pH † ̄‹j 0 †_‡K 14 ch©šÍ nq †Kb? [JnU 18-19] 60| †Kv‡bv `ae‡Yi pH 1.4 n‡j D3 `ae‡Y [H+ ] Avqb Gi NbgvÎv wbY©q Ki Ges 1% NaOH `aeY Gi pH wbY©q Ki| [KU 15-16] DËi: 13.39794 61| evdvi `aeY Kx? pH Kx? 62| `ae‡Yi H3O + Avq‡bi NbgvÎv 1.0 M Gi †ewk n‡j pH † ̄‹j AKvh©Ki nq †Kb? 63| HNO3 GwmW I H3PO4 Gwm‡Wi g‡a ̈ †KvbwU AwaK kw3kvjx e ̈vL ̈v Ki| 64| AmIqvì-jNyKiY m~ÎwU MvwYwZK iƒcmn †jL| 65| cvwbi AvqwbK ̧Ydj †_‡K Kxiƒ‡c pH † ̄‹j •Zwi Kiv nq? 66| Zxea GwmW I Zxea ÿv‡ii cÖkgb Zvc aaæeK †Kb? 67| NaOH Ges HF Gi cÖkgb Zv‡ci gvb aaæeK gv‡bi †P‡q †ewk †Kb? 68| 0.75 M H3PO4 Gi Rjxq `ae‡Yi pH KZ? [pKa = 2.2] DËi: 0.461955 69| CH3 – COOH Gi Rjxq `ae‡Yi †Kvb NbgvÎvi pH Gi gvb, 0.25 M NbgvÎvi H – COOH Gi Rjxq `ae‡Yi pH Gi gv‡bi mgvb| KH-COOH = 1.8  10–4 Ges KCH3 – COOH = 1.8  10–5 DËi: 2.5 M 70| cÖ‡Z ̈K NbgvÎvq H2SO4 I NaOH Gi pH wbY©q Ki| (i) 4900 ppm H2SO4 (ii) 0.025 M NaOH (iii) 1%     w v NaOH (iv) 10–8 M NaOH DËi: (i) 1; (ii) 12.398; (iii) 13.39; (iv) 7.041 71| 1%     w v Na2CO3 Gi pH wbY©q Ki Ges OH– Avq‡bi NbgvÎv wbY©q Ki| DËi: 13.27 72| 1.0 M wg_vBj A ̈vwgb `ae‡Yi pH MYbv Kiv| (Kb = 14.17 ×104 )| DËi: 12.29 73| M 5 †ewiqvg nvB‡Wav·vBW `ae‡Yi pH KZ? DËi: 13.602 74| 25C [CH3 – COOH] = 0.01 M pH = 4 25C [NH4OH] = 0.01 M DÏxc‡Ki Dfq cv‡Îi `a‡ei we‡qvRb gvÎv GKB| 2q cv‡Îi `ae‡Yi pH gvb wbY©q Ki| DËi: 10 75| 10–7 M HCl Gi pH = ? 10–6 M HNO3 Gi pH = ? DËi: 5.96
ivmvqwbK cwieZ©b  Varsity Practice Sheet 5 76| 10–3 M NaOH (2L) I 10–2 M KOH (1L) wgkÖYwUi pH KZ? DËi: 11.6 77| 10–2 M HCl (2L) I 10–3 M NaOH (1L) wgkÖYwUi pH KZ? DËi: 2.2 evdvi `aeY 78| GK †gvj A ̈vwmwUK GwmW I GK †gvj †mvwWqvg A ̈vwm‡UU m¤^wjZ GK wjUvi `ae‡Y 4 g NaOH `aexf~Z Kiv nj| Drcvw`Z wgkÖYwUi pH wbY©q Ki| [A ̈vwmwUK Gwm‡Wi we‡qvRb aaæeK = 1.8  10–5 ] [BUET 19-20] DËi: 4.832 79| 400 ml 0.1 M NaOH Gi mv‡_ 600 ml 0.2 M A ̈vwmwUK GwmW †hvM K‡i GKwU evdvi `aeY cÖ ̄‘Z Kiv nj| evdvi `ae‡bi pH KZ? (A ̈vwmwUK Gwm‡Wi Rb ̈: pKa = 4.76) [BUET 17-18] DËi: 4.46 80| 4.60 pH Gi GKwU evdvi `aeY •Zwi Ki‡Z n‡e| GRb ̈ GKwU weKv‡i 0.01 M A ̈vwmwUK GwW‡mi 10.0 mL `aeY †bqv nj| G‡Z 0.01 M †mvwWqvg A ̈vwm‡U‡Ui KZ AvhZb (mL) `aeY †hvM Ki‡Z n‡e? [pKa = 4.75] [BUET 12-13] DËi: 7.079 mL 81| 60 cm3 0.05 M CH3COOH `ae‡Yi mv‡_ KZ cm3 0.1 M CH3COONa `aeY †hvM Ki‡j `ae‡Yi pH 4.0 n‡e? [Ka = 1.8  10–5 ] [BUTex 21-22] DËi: 5.4 cm3 82| evdvi `aeY (buffer solution) ej‡Z Kx eyS? ÿvixq evdvi `ae‡Yi pH wKfv‡e wbqš¿Y K‡i D‡jøL Ki| [JnU 18-19] 83| Òi3 n‡jv GKwU evdvi `aeYÓ Ñ e ̈vL ̈v Ki| 84| B_v‡bvwqK GwmW (CH3 – COOH) Gi 1 M NbgvÎvi `ae‡Yi mv‡_ †mvwWqvg B_vb‡qU (CH3 – COONa) 1 M Gi NbgvÎvi `aeY wgwkÖZ K‡i 5.05 pH gv‡bi evdvi `aeY cÖ ̄‘Z Kiv n‡jv| 600 mL AvqZ‡bi G evdvi `aeY cÖ ̄‘Z Ki‡Z n‡j KZ AvqZ‡bi CH3 – COOH cÖ‡qvRb wbY©q Ki| (Ka = 1.8  10–5 ) DËi: 200 mL 85| 4.75 pH Gi GKwU evdvi `aeY •Zwi Ki‡Z 0.02 mol †cÖvcvbwqK GwmW aviYK...Z 1.0 dm3 GKwU `ae‡Y KZ †gvj †mvwWqvg †cÖvcvb‡qU †hvM Ki‡Z n‡e? [Ka = 1.33 × 10–5 ] DËi: 0.01496 mol ivmvqwbK wewμqvi kw3i iƒcvšÍi 86| hw` cvwbi MVb Zvc 25C ZvcgvÎvq – 68370 Cal nq Z‡e 60C ZvcgvÎvq Zv KZ n‡e? †`Iqv Av‡Q, Cp (H2) = 6.90 Cal mole–1 C –1 , Cp(O2) = 7.05 Cal mole–1 C –1 Ges Cp (H2O) = 18.0 Cal mole–1 C –1 [BUET 17-18] DËi: – 68104.875 Cal 87| wewfbœ cÖKvi Gb_vjwc cwieZ©‡bi bvg wjL| Kve©b, nvB‡Wav‡Rb Ges wPwbi `nb Zv‡ci gvb h_vμ‡g – 406 kJ, – 284 kJ Ges –5638.82 kJ| wPwbi MVb Gb_vjwci gvb wbY©q Ki| [KUET 08-09] DËi: – 2357.18 kJ mol–1 88| NO2 Gi ms‡kølY wewμqvi mgxKiY n‡jv wb¤œiƒc : N2 (g) + 2O2 (g) ––– 2NO2 (g); H = ? wb‡Pi wewμqv `ywU e ̈envi K‡i NO2 Gi wewμqv Zvc MYbv Ki : N2 (g) + O2 (g) ––– 2NO (g); H = + 180 kJ 2NO2 (g) ––– 2NO (g) + O2 (g) H = + 112 kJ DËi: + 68 kJ 89| †n‡mi m~Î cÖ‡qvM K‡i wb¤œwjwLZ wewμqvi Gb_vjwci cwieZ©b (H) wbY©q Ki| C (MÖvdvBU) + 2H2(g)  CH4(g) †`Iqv Av‡Q: (i) CH4(g) + 2O2(g)  2H2O(l) + CO2; H1 = – 849.65 kJ .......... (i) (ii) C (MÖvdvBU) + O2(g)  CO2(g); H2 = –406.13 kJ ..... (ii) (iii) H2(g) + 1 2 O2(g)  H2O(l); H3 = – 241.82 kJ ...... (iii) [KUET 05-06] DËi: – 40.12 kJ ---