Chemistry Exam with Verified Answers and Scientific Inquiries, Exams of Chemistry

Download Chemistry Exam with Verified Answers and Scientific Inquiries and more Exams Chemistry in PDF only on Docsity! CHEM120 FINAL EXAM OF 54 QUESTIONS WITH VERITIED ANSWERS GRADED A+ 1. The name of the compound FES04 is iron sulfate 2. Peptide bonds link the amino acids together to make a primary polypeptide sequence. The bonds are AMIDE 3. If a balloon is filled with helium were heated with a blow dryer , the balloon would increase in volume 4. You are setting up an experiment to test a pair of experimental headache medications, X & Y . As part of the experiment setup, you take individuals suffering from headaches and divide them into 4 groups and provide each with a different pill. Which of the 4 groups below would you classify as the positive control? A group given the placebo pill 5. Which of the following is not normally part of the scientific inquiry? Philosophizing 6. An isotope has a total of 46 neutrons and 22 protons. What would be the atomic symbol of this isotope? Ti (Titanium) 7. Which of the following is the correct formula for nitride ion? N3- 8. Select all that would be classified as cations. Magnesium, Li+ 9. An isotope of gallium (atomic number 31) has a mass number of 67 . How many neutrons will this isotope have? 36 10. Select all of the following that would be classified as polar covalent compounds: PCl3,H20 11. Select all of the following compounds that would be classified as ionic : Sodium Chloride, Ca3N2,CaF2 12. Which of the following would you expect to form when a nickel(I) ion combines with nitrate? NiNO3 13. Calcium Phosphate, Ca3(PO4)2 is used to treat calcium deficiency . What is the molar mass of this compound? 310.18g/mol 14. Determine the number of oxygen atoms in magnesium hydroxide: 2 15. Xenon gas reacts with fluorine gas to form xenon tetrafluoride. Identify which image in the figure represents the reactants and which image represents the products in the correct ratio so that mass is conserved. Option that states Image A shows reactants and image C shows products 16. Balance the following skeletal equation: Li(s) + H20(l)  LiOH(aq)+H2(g) 2Li(s)+2H20(l) 2LiOH(aq)+H2(g) 17.Which of the following units can be used to represent the concentration of a solution prepared by dissolving salt in water. Select all that apply : M(mol/liter) , % mass by volume 18. A solution of ethanol ,C2H5OH is prepared by dissolving 25.0 ml of ethanol in enough water to give a total volume of 250.0 ml .What is the percent by volume concentration of ethanol ? 10% 19. How many liters of 8 M NaCl solution would you need to add to a reaction that requires 2 moles of NaCl ? 0.25 L 35. At a fixed temperature, a sample of gas is moved entirely from a smaller container to a larger container. You would expect: Pressure to decrease. 36. You would like to prepare an 8L of a 0.25 M HCl solution. How many liters of a 4.5 M HCl solution would you require? SHOW ALL WORK M1V1 = M2V2 M1 – 0.25 M HCl M2- 4.5 M HCl V2 = 0.25x 8L /4 V2 = 0.44 L 37. Math the condensed structure of the chemical compound to the correct functional group CH3CH2CH2CHCH2- ALKENE CH3CH2CH2COOH-CARBOXYLIC ACID CH3CCH-ALKYNE CH3COOH3-ESTER CH3CH2CH2OCH2CH3-ETHER 38. Match the organic compound to the corresponding use or application Butane -Fuel Propane (acetone) – nail polish remover Phenol- antiseptic Methyl Salicylate – wintergreen flavor Butanoic acid- fatty acid in butter 39. Given the formula of the compound CH3CH2CH2OH, determine the name of the functional group, give the correct carbon chain prefix , and give the name of the organic compound Functional group – alcohol Organic compound- 1- propanol Carbon chain prefix- prop 40. An isotope of a potassium with an atomic number of 19 and a mass of the number 40 undergoes beta decay. Give the resulting chemical symbol , and mass number of the resulting atom(decay product) Symbol Ca Atomic # 20 Mass # 40 41. You will be working with a radioactive isotope as part of your job duties. Which of the following radioactive processes would require the greatest amount of shielding to protect you from radiation exposure? Gamma ray radiation 42. Provide 2 applications or uses of radioactive isotopes: Iodine 131 – used to treat overactive thyroid disease and thyroid cancer Carbon 14 -study metabolism changes for patients with diabetes, gout and anemia Chromium 51 – track red blood cells , quantify protein in blood loss 43. Balance the chemical equation C5H12+ O2CO2+H20 C5H12+8O25CO2+6H20 44. You preform the reaction below and obtain 6.00 grams of H20.How many grams of NH3 did you react to form this product? 2NH3(g)+3CuO(s) 3Cu(s)+N2(g)+3H20(l) SHOW ALL WORK H =1.008(2) + O 16 =18.06 g/moles N =14.0 + H ; 1.008(3) =17.034 6gx 1 molex 2mole of NH3 x 17.03g /18.06 g x 3 moles of H20 x 1 mole of NH3 =3.78 g 45. Balance this reaction, then determine the element that is being oxidized ; Al +H2S Al2S3 + H2 2Al+3H2SAl2S3+3H2 Al is being oxidized 46. Determine which specie is acting as an acid in the forward direction; CH3COOH+H20 > CH3COO- + H30+ CH3COOH 47. Select all solutions that would be considered acidic Solution with a proton concentration of 1x 10 -4 M (H)+, Solution with a ph of 2 48. Match the expected shape to the compound CO2- linear CH20-trigonal planar CBr4 -tetrahedral P13-trigonal pyramid