1. how many significant figures does the sum of the following contain? 8.520 + 2.7
3. the oxidation number of N in NaNo3 is
4. what element is oxidized in the following chemical reaction? 3Cu + 8HNO3 ----> Cu(NO3) + 2NO + 4H2O
7. which of the following ions has the largest radius Na+, K+, Ca2+, Cl-, F-
8. which one of the following molecules does not have a dipole moment: CO, CH2Cl2, SO3, SO2, NH3
for the rest of the problems work out and observe significant digits
9. The freon propellant from an aerosol can was analyzed, and a 4.263g sample contained the following: 0.423 g carbon, 2.50 g chlorine, and 1.34 g fluorine. The molecular weight of the propellant is 244 g/mol. What is the empirical formula of the compound? What is the molecular formula of the compond?
11. What volume of carbon dioxide gas can be collected from the reaction between 10.0g of calcium carbonate and 100.0 mL of 0.50 M hydrochloric acid at 25.0C and 1.0 atm pressure? R=0.082 L *atm/K*mol