Assignment:
Question 1. Pennies made after 1982 contain 97% zinc by mass. A student wants to prove this by filing the copper outside the penny until he sees zinc and then putting the penny in a 1.00 M HCl solution. The zinc will be oxidized and the H+ (from the HCl) will be reduced:
Zn + 2H+ ----- Zn2+ + H2
If the entire penny has a mass of 2.80 grams, how many ml of 1.00 M HCl are required to just react with all the zinc? ( You would, in reality, add much more to completely surround the penny)
Question 2. Determine the oxidation number for each atom in the following compounds:
a.) MgBr2 c.) Cr2O7 e.) NaClF4
b.) Na2SO4 d.) CaCO3 f.) HNO3
Provide complete and step by step solution for the question and show calculations and use formulas.