Grade 8. National Chemistry Competition First Round Mehmet Akif College. International School of Prishtina
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1 Mehmet Akif College IS International School of Prishtina INSTITUCIONET ARSIMORE GÜLISTAN National Chemistry Competition First Round Grade 8
2 UDHËZIMET PËR GARAT KOMBËTARE TË KIMISË 2015 Keni 80 minuta për t u përgjigjur në 50 pyetje. Çdo përgjigje e saktë vlerësohet me 1 pikë. Për çdo përgjigje të gabuar 0,25 pikë do të zbriten nga rezultati juaj përfundimtar. Nuk ka ndëshkim për pyetjet e papërgjigjura. Çdo pyetje e ka një përgjigje të saktë Pasi që të filloj testi nuk ju lejohet që të dilni jashtë në 30 minutat e parë. Telefonat dhe kalkulatorët nuk lejohen gjatë testit.
3 National Chemistry Competition (First Step) Grade 8 1. Numri i atomeve në molekulen e ujit është: A) 2 atome hidrogjen - 1 atom oksigjen B) 1 atom hidrogjen - 2 atome oksigjen C) 1 atom helium - 2 atome oksigjen D) 2 atome hidrogjen - 2 atome osmium E) 3 atome hidrogjen - 1 atom oksigjen 2. Cila prej lëndëve nuk i takon shkencave natyrore? A) Fizika B) Kimia C) Biologjia D) Matematika E) Gjeografia 7. Vlera e numrit të Avogadro's është: A) 3,14 B) 8,314 C) 6,02 x D) 22,4 E) Në elemente NUK bëjnë pjesë: A) Metalet B) Jometalet C) Metaloidet D) Acidet E) Metalet alkaline 3. Perqindja në masë e gazit të oksigjenit në ajer është: A) 10% B) 21% C) 90% D) 78% E) 23% 4. Cila nga të poshtë shënuarat NUK është materie? A) Lapsi B) Uji C) Ajri D) Nxehtesia E) Dielli 5. Si quhet tabela e ndërtuar nga elementet kimike? A) Tabele trigonometrike B) Tabele periodike C) Tabele logaritmike D) Tabele multiaplikative E) Tabele per matjen e kohes 6. Cili nga të poshtë shënuarit NUK është element? A) Ca B) CO C) O D) Co E) K 9. Cila është formula e akullit? A) CO 2 B) H 2 O C) O 2 D) H 2 E) CJ Pjese e atomit NUK është: A) Fotoni B) Elektroni C) Neutroni D) Protoni E) Bërthama 11. Në gjendje agregate të materies NUK bën pjesë: A) Moli B) Trupi i ngurtë C) Lëngu D) Gazi E) Plazma 12. Cila prej vetive të poshtëshënuara NUK është e saktë për acidet : A) Japin jonine H + ne uje B) Mund te reagojne me metalet amfoterike C) Neutralizohen me baza D) disa prej acideve jane; HCl, CH 3 COOH dhe H 2 SO 4 E) Letren e lakmusit e ngjyrosin ne te kalter 2 Gülistan Educational Institutions Mehmet Akif College International School of Prishtina
4 Grade 8 National Chemistry Competition (First Step) November 14, Sa gram SO 3 dhe H 2 O nevojiten për të përgatitur 400 g tretësire të H 2 SO 4 49%? (H=1, S=32, O=16) m(so 3 ) m(h 2 O) A) B) C) D) E) Cila prej zgjidhjeve të përshkruara më poshtë është e saktë? I- Grimcat e tij lëvizin shumë shpejt dhe shpërndahen në të gjitha drejtimet. II- Ka forme të caktuar dhe nuk mund të kompresohet. III- Merr formën e enes,ka vlerë energjetike të lartë. I - II - III A) I ngurtë - Lëng - Gaz B) Leng - I ngurtë - Gaz C) Gaz - I ngurtë - Leng D) Gaz - I ngurtë - Gaz E) I ngurtë - Gaz - Leng 15. Sa është densiteti i një objekti në formë të kubit që ka gjatësine e siperfaqës 10 cm dhe masë prej 19.3 kg? A) 1,93 g/ml B) 19,3 g/ml C) 19,3 kg/ml D) 193 g/l E) 1930 g/ml 16. Sa është përqindja (%) në masë e oksigjenit në CuSO 4 5H 2 O. (Cu=64, S=32, O=16, H=1) A) 47.8% B) 57.6% C) 64.2% D) 55.3% E) 14.4% 17. Kur reaksionin e poshtëshënuar e barazojmë: Al 2 O 3 + H 2 SO > Al 2 (SO 4 ) 3 + H 2 O Sa është shuma e koeficienteve? 18. 1,5 g e legurës të Cu dhe Mg reagojnë me HCl në tepricë dhe fitohen 0.56 L gaz te H 2 ne K.S. (kushte standarde) Sa është përqindja në masë e Cu në legurë? (Cu=64, Mg=24) A) 60% B) 40% C) 20% D) 30% E) 10% 19. Sa është numri oksidues i N në NaNO 3, AlN dhe NH 4 Cl? A) +3, -3, +3 B) +5, +3, -3 C) +3, -1, +3 D) +5, -3, -3 E) -3, -3, Jonet X +2 dhe Y -3 kanë numër të njejtë të elektroneve. Sa është numri i protoneve te Y, nëse numri atomik i X është 12? A) 18 B) 15 C) 12 D) 10 E) Cili nga reaksionet e poshtëshenuara jep kripë acidike? A) KOH + HF B) HCl + NH 3 C) HJ + NaOH D) NaH + H 2 O E) KOH + CH 3 COOH 22. Sa është masa e CO 2 i cili përmban 64 g oksigjen? (C=12, O=16) A) 44 B) 72 C) 88 D) 76 E) 104 A) 8 B) 4 C) 10 D) 6 E) 5 Mehmet Akif College International School of Prishtina Gülistan Educational Institutions 3
5 National Chemistry Competition (First Step) Grade Gjeni masën e C ne 44.8 L të gazit te C 3 H 8 në K.S (kushte standarde) (C=12, H=1) A) 6 B) 12 C) 24 D) 48 E) ,8 g të X 2 O zënë vëllimin prej 4,48 L në K.S. (kushte standarde) Gjeni masën atomike të X? (O=16) A) 24 g/mol B) 52 g/mol C) 14 g/mol D) 80 g/mol E) 32 g/mol 25. Llogaritni sasinë e ajrit (L) që nevojitet për djegien e 4.48 L të gazit të CH 4 në K.S (kushte standarde) sipas reaksionit: (Dimë se 1/5 e volumit të ajrit është oksigjen) CH 4 + 2O > CO 2 + 2H 2 O A) 11.2L B) 22.4L C) 2.24L D) 33.6L E) 44.8L 26. Cilat gaze e formojnë shiun apo të reshurat acidike? A) CO 2 dhe H 2 B) CO dhe N 2 O C) SO 2 dhe NO 2 D) O 2 dhe N 2 E) N 2 dhe H 2 O 27. Është dhënë reaksioni; X + 3O > 2CO 2 + 3H 2 O Gjeni formulen kimike të X? A) C 2 H 4 B) C 3 H 8 C) C 3 H 10 O D) C 2 H 5 OH E) C 2 H Cila nga substancat e dhëna NUK përmban vetëm një lloj te atomeve apo molekulave? A) Uji B) Sulfuri C) Hekuri D) Acidi acetic E) Uji i njelmet 29. Jane dhënë më poshtë disa shembuj të elementeve, komponimeve dhe përzierjeve; I. Elemente: Bakëri, Hekuri, Hidrogjeni II. Komponime: Uji, Ajri, Karboni III. Perzierje: Dheu, Qumeshti, Akullorja Gjeni zgjidjen e SAKTE? A) Vetëm I B) I dhe II C) II dhe III D) I dhe III E) I, II dhe III 30. Formula e kripës së kuzhinës është: A) Na B) SCl 6 C) NaCl D) SCl 3 E) CaCl Reaksioni i neutralizimit është: A) Reaksioni në mes dy jometaleve B) Gjatë këtij reaksioni lirohet nxehtësi dhe dritë C) Reaksioni në mes acidit dhe bazës D) Reaksioni në mes një oksidi dhe ujit E) Reaksioni në mes kripës dhe ujit 32. Cili nga komponimet e paraqitura nuk është acid ose bazë e fortë? A) KOH B) NaOH C) H 2 SO 4 D) HF E) HCl 4 Gülistan Educational Institutions Mehmet Akif College International School of Prishtina
6 Grade 8 National Chemistry Competition (First Step) November 14, Tabela periodike është përpiluar në bazë të të atomeve. A) numrit atomik B) masës atomike C) numrit të neutroneve D) vetive kimike E) ngarkesës së berthames 34. Cila grimcë subatomike nuk ka ngarkesë? A) Elektroni B) Neutron C) Protoni D) te gjitha më lart E) asnje më lart 35. Izotopet natyrale të Uraniumit janë U-238, U-235 dhe U-234. Nëse numri protonik i U është 92, çfarë vlera do të ketë numri i neutroneve për izotopet e cekura? U U U-234 A) B) C) D) E) Cilat nga shpjegimet e dhëna më poshtë janë të SAKTA për elementet e sistemit periodik? I - Energjia e jonizimit të atomeve rritet nga e djathta në të majtë. II- Energjia e jonizimit të atomeve rritet nga lartëposhtë. III-Radiusi atomik i atomeve rritet nga e djathta në të majtë. IV-Radiusi atomik i atomeve rritet nga lartë-poshtë. A) I-III B) I-II C) I-II-III-IV D) III-IV E) I-II-III 37. Sa perioda (P) dhe sa grupe A (GA) janë në sistemin periodik? P GA A) 6 6 B) 7 8 C) 8 7 D) 7 6 E) Bateria për elektrolize ka dy elektroda që njihen si: A) Elektron-Tretësirë B) Kation-Anion C) Elektrolit-Joelektrolit D) Katode-Anode E) Elektricitet-Tretësirë 39. Cili nga reaksionet e poshtëshënuar liron GAZ gjatë reaksionit të substancave në mes veti? A) MgCl 2 + Ba(NO 3 ) > B) Na 2 CO 3 + CaCl > C) NH 4 Cl + NaOH ----> D) CuSO 4 + KOH ----> E) Al 2 O 3 + NaOH ----> 40. ZnO mund të reagojë me njërin nga ciftet e poshtëshënuara. Gjeni me cilin? A) Na 2 O dhe H 2 O B) SiO 2 dhe Ag C) NaOH dhe HCl D) C dhe N 2 E) HNO 3 dhe O Cili nga ciftet e më poshtme është izoelektronik? A) Al 3+ dhe N 3- B) K + dhe F - C) Ca 2+ dhe Cl 5+ D) S 0 dhe Cl - E) N 3- dhe P3 - Mehmet Akif College International School of Prishtina Gülistan Educational Institutions 5
7 National Chemistry Competition (First Step) Grade Tretshmëria e X ne 80 o C është 25 g dhe ne 60 o C është 20 g. Sa g kripe do te fitohet nëse 60 g të tretësirës të ngopur së X në 80 o C ftohet në 60 o C? A) 12 B) 9,6 C) 2,4 D) 2 E) 3,2 47. E anuluar 48. E anuluar 49. E anuluar 50. E anuluar 43. Cili nga reaksionet e poshteshënuara quhet reaksion i djegies? A) H 2 + Cl > 2HCl B) Ca + 2HCl ----> CaCl 2 + H 2 C) C 2 H 6 + 7/2O > 2CO 2 + 3H 2 O D) 2KClO > 2KCl + 3O 2 E) 3CaO + 2H 3 PO > Ca 3 (PO 4 ) 2 + 3H 2 O 44. Cila do të jetë shuma e koeficienteve të reaksionit të poshtëshënuar pas barazimit? A) 18 B) 10 C) 15 D) 13 E) 20 Cu + HNO 3 ---> Cu(NO 3 ) 2 + NO 2 + H 2 O 45. Cilat metale njihen si metale tranzitore? A) Metalet alkaline B) Metalet e grupit 2A C) Metalet e grupit B D) Halogjenuret E) Metaloidet 46. Nëse nje metali alkalin i shtojmë uje, çfare ngjyre do të merr letra e lakmusit? A) Të kuqe B) Të kaltër C) Pangjyrë D) Të verdhë E) Të gjelbër 6 Gülistan Educational Institutions Mehmet Akif College International School of Prishtina
8 INSTITUCIONET ARSIMORE GÜLISTAN International School of Prishtina Marigona Residence, Prishtinë ; ispkosova.com; Mehmet Akif College - Lipjan Banullë, Lipjan ; mackosova.com; info@mackosova.com Mehmet Akif College - Gjakovë Rr. Zidi Sadiagas, ish TMK ; macgjakova.com info@macgjakova.com Mehmet Akif College - Prizren Boka, Korishë, Prizren ; macprizren.net; info@macprizren.net Kopshti i Fëmijeve YLLKA Lagja Bazhdarhane Rr. Asdrenit nr.14, Prizren ; yllka.net; info@yllka.net
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