CHEM 121 Exam Solutions Winter 2018: Sodium Oxide, Isoelectronicity, Atomic Number

• School: UBC
• Department: Chemistry
• Course: CHEM 121
• Professor: All

Document Summary

Put the first letter of your family/last name in this box. Instructions: write all answers on this examination paper, and show full details of your solutions for part 2, read each question carefully, check that this examination consists of 12 pages printed on both sides. The last sheet (pages 11 and 12), containing supplementary information and the periodic table may be detached for ease of use: the only calculator allowed is the sharp el-510rb. Cell phones or other electronic communication devices are not permitted: unassembled molecular model kits may be used. For each numbered statement below, write the letter that corresponds to the best answer. There is only one correct answer per question. Lewis structure? (the underlined atom is the central atom. ) (a) hcn (b) oncl (c) [nbcl] (d) ni3 (e) n2o. Answer: bromine, with an atomic weight of 79. 90 g mol 1, has only 2 stable isotopes.