CHEM 121 Midterm: CHEM121 Midterm 2 2011 Fall Solution

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

Document Summary

For each numbered statement below, circle the letter that corresponds to the best answer. There is only one correct answer per question. 6 marks: for this question, consider only the following elements as possible answers: For each part, give the symbol from the above list that makes the statement correct. Answers may be used more than once. (a) __al_____ is involved in the thermite reaction. (b) __ p____ exists as an allotrope with only one lone pair per atom. (c) __ar___ is isoelectronic with si in mg2si. (d) __ p___ exists as an allotrope that ignites spontaneously in dry air. (e) ___s___ commonly has an oxidation state of +2, +4, or +6 in compounds. 8 marks: complete and balance the following reactions (assume sufficient heat is present to give a reaction no reaction is not an acceptable answer): (a) _2__ h2s + ___ so2 3s +