Model (C) King Abdul Aziz University Faculty of science Chemistry department. Chem.110 Final exam of 1 st term H Time: 120minutes

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1 King Abdul Aziz University Faculty of science hemistry department Model () hem.110 Final exam of 1 st term H Time: 120minutes Student name: Student number Section Useful information Speed of light, Planck s const., c = m/s h = J.s Avogadro s No., N A = mol -1 Rydberg const. for H atom, R H = J Gas constant, R= L atm K -1 mol -1 With the best wishes General hemistry Team work 1

2 Directions: For each of the following questions, choose the letter that best answers the question and place it on your answer sheet. 1.The diameter of a circuit is 11 X 10 3 cm. What is this diameter when expressed in micrometers? 11 X 10 5 µm 11 X 10 7 µm 11 X 10 3 µm 11 X 10 9 µm 2. How many milliliters in L? ml ml ml ml 3. Bromine is a red liquid at 25. Its density is 3.12 g/cm 3. What is the volume of 42.5 g of liquid bromine? cm cm cm cm 3 4.Which of the following is a SI base unit? candela hour yard all of the above 5.Which of the following element is in the halogen group? N Li Mg Br 6.Which pair of Atomics would be most likely to form a molecular compound? Li and N K and l Li and K and O 2

3 7. Give the number of protons (p), electrons (e), and neutrons (n) in fluoride ion, 9 19 F -. 9 p, 10 n, 10 e 10 p, 10 n, 9 e 10 p, 9 n, 10 e 9 p, 10 n, 8 e 8. What is the mass of 0.46 mol nickel (Ni) metal? g g g g 9. How many grams of l 2 can be prepared from the reaction of 15.2 g of MnO 2 and excess of Hl according to the chemical equation: MnO 2 + 4Hl Mnl 2 + l 2 + 2H 2 O 11.4 g 12.4 g 15.4 g 10.4 g 10. alculate the molarity of a solution of 6 g of ethanol ( 2 H 5 OH) in 546 ml of solution M 1.3 M 1.24 M 0.24 M 11. How many bonds around phosphorous atom in, NF 3? The formal charge on Boron atom in, H 4?

4 13.The type of bond in l 2 ompound can be classified as Polar covalent bond Ionic bond Hydrogen bond Nonpolar covalent bond 14. How many total valence electrons are present in, H 2 O 3? The electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 applies to all of the following species except: a 2+ K + Na + Ar 16. The correctly drawn Lewis formula for l 4 will have. 4 single bonds and 12 nonbonding electrons 4 single bonds and 20 nonbonding electrons 4 single bonds and 18 nonbonding electrons 4 single bonds and 24 nonbonding electrons 17. Which one of the following molecules would exhibit resonance? O 3 H 2 S l 2 H Which of these molecules has an expanded of the octet rule? NF 3 Pl 5 Br 2 O 4

5 19. If the initial pressure of a 2.00 L gas sample is 2.50 atm, what will the pressure be if the volume is changed to 3.00 L at constant temperature? atm 1.50 atm 1.67 atm 3.75 atm 20.Propane burns in air according to the equation: 3 H 8 (g) + 5O 2 (g) 3O 2 (g) + 4H 2 O(g) What volume of O 2 would be formed if 8.00 L of propane burns, assuming that all of the gases are under the same conditions? 12.0 L 24.0 L 3.00 L 4.80 L 21. Select the correct equilibrium constant expression for the reaction: Keq = [S 2 ][H 2 ] 4 / [H 4 ][H 2 S] 2 Keq = [H 4 ][H 2 S] 2 / [S 2 ][H 2 ] 4 Keq = [H 4 ][ H 2 S] / [S 2 ][H 2 ] Keq = [S 2 ][H 2 ] / [H 4 ][H 2 S] H 4 (g) + 2H 2 S(g) S 2 (g) + 4H 2 (g) 22. Select the solution below that is the most acidic. [H3O + ] = M [H + ] = M [H + ] = M [H + ] = M 23. onsider the following system at equilibrium: H 4 (g) + 2H 2 O (g) O 2 (g) + 4H 2 (g) What change will cause the equilibrium to shift to form more H 4? add a catalyst decrease [H 2 O] increase the volume of the reaction vessel decrease [H 2 ] 5

6 24. onsider the following system at equilibrium: 2 H 2 (g) + H 2 (g) 2 H 6 (g) Exothermic What change will be observed if the temperature of the reaction mixture at equilibrium were increased? The concentration of 2 H 6 will increase. The concentration of both 2 H 2 and H 2 will increase. There will be no change in the equilibrium concentrations. The concentration of both 2 H 2 and H 2 will decrease. 25. alculate the ph of a solution that has [H 3 O + ] = M. ph = 1.00 ph = ph = 7.00 ph = If the ph of a solution is 11, the solution will be: Acidic Neutral Alkaline None of these 27. Fill in the blanks: 6.00 moles of oxygen gas (O 2 ) have a weight of g, and occupy volume of L at STP. 192 g, 134.3L 64.0 g, 22.4 L 64.0 g, 3.00 L 96.0 g, 67.2 L 28. The reaction in which increased pressure has no effect on the equilibrium reaction is O 2 (g) + H 2 (g) O(g) + H 2 O(g) N 2 (g) + 3 H 2 (g) 2 NH 3 (g) 2 H 2 (g) + O(g) H 3 OH(L) ao 3 (s) ao(s) + O 2 (g) 6

7 29. The equilibrium constant for the following reaction: N 2 (g) + 3H 2 (g) 2NH 3 (g) is 70 at 350 o. A system at equilibrium has [N 2 2] = 0.2 M and [H 2 ] = 0.1 M. What is the [NH 3 ]? 30. Kc will be equal to Kp if. 31. The correct order of radius in the following is n = 1 n = 0 RT = 0 n = l - < l O -2 < O Fe +2 > Fe Fe +2 > Fe e which of the following compounds is aromatic?( H 3 -H 2 -H 3 H 3 -H 2 =H 2 H3- H Whichh of these elements has the lowest electronegativity? 34. The nickel (II) ion, Ni 2+, has how many 3d electrons? 51Sb 33As 31Ga 55s

8 35. Which one of these elements (period 4) is a transition element? Br As a Zn 36. The correct order in the first ionization energy is: N <O < < Si Si < <O <N O > N > > Si > N > O > Si 37. The general formula of an alkene is 38. The functional group in this compound H 3 H 2 H 2 H 2 OH is n H 2n+2 2n H 2n n H 2 n n H 2n-2 Alcohol Aldehydee Amine Ether 39. A protein is a polymer of ester. a polymer of amino acids. an aromatic hydrocarbon. none of these. 40. Which of these is the systematic name for the compound represented below? 3-methylpentane 2-ethylbutane 2-methylpentane 3-ethylbutane 8

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