Chemistry 500, First Mid-Term Exam Spring 2000 Dr. Hunter Your Name: , Student Number1: last first For all of the questions on the following four pages, make sure you clearly explain your reasoning and show your work. You may use a calculator (you may not program information into your calculator) but may not use any other outside materials such as books or notes. If you are unsure of how to interpret any of the questions, please ask me for help. On some of the following questions, you have a choice of which parts to answer. Circle the letters of the parts you want me to mark. When you are done, please hand your exam in to me at the front and then either wait quietly in your desk or in the hallway. This exam is scheduled for the final 50 minutes of class. Total Grade: /50 (i.e. 25% of the final grade) 1 Note: Your student number is your social security number.21. (10 marks in total) For two out of three of the following questions, give a short answer in the space provided. Clearly show which ones you want me to grade. Show your reasoning and/or your work. a. Estimate the daily volume of air you breathe. Show your work IN DETAIL!!! b. Give the number of significant figures for each of the following clearly describing how you come to this answer. If you wanted to do an accurate calculation, which number would you use (give me your reasoning). 331,267 → 3.31 x 105 → 3 x 105 → c. What factors contribute to Los Angles having particularly high levels of pollution?32. (15 marks in total) Balance each of the following reactions. Show your work!!!!! a) P4 + S8 → P3S5 b) C3H8 + Cl2 → C3H3Cl5 + HCl c) C6H10 + O2 → CO2 + H2O43. (15 marks in total) For each of the following molecules, determine the expected number of valence electrons, draw the Lewis structure, and check if your Lewis structure is correct. a) H C C O O C C F b) H H H H C C S C C N H c) Cl H H H H P O C C O Si H Br H H54. (10 marks in total) For each of the following isotopes, give the total number of protons, neutrons, and electrons and then the number of valence electrons and core electrons. Show your work. a) 13C total number of neutrons = total number of protons = total number of electrons = number of valence electrons = number of core electrons = b) 21F total number of neutrons = total number of protons = total number of electrons = number of valence electrons = number of core electrons