I'm going to try and give this a go.
1. 1 because Na is the element symbol and the atomic number is on side at the bottom while the mass is on the top.
2. 4. Sr because Ca and it are on the first column together, thus they are in the same family with similar chemical properties.
3. 4. Tin is a metal, thus it is malleable. THe others are nonmetals.
4. 2. Isotopes differ in neutrons. Ions, on the other hand, differ in electrons.
5. Not sure. O2 is a oxygen in diatomic form. O3 is ozone.
6. 3. Fe 2+ and S 2-. Cross the electrons and you should get FeS. Thus, iti si Iron (II) Sulfide.
7. 2. It is 1:2 because for every one mole of H2, you produuce 2 moles of HF.
8. Process of elimination. It can't be 1 and 2 because condensation concerns intermolecular forces, not chemical reactions. 4 is wrong as well. Answer is 3.
9. 2. Ionic b/c metals give the nonmetal the electrons. Metallic bonds have a sea of electrons and covalent shares.
10. I can't tell if that is a triple bond b/c the pic is too small. If it is, the answer is 1: 6 electrons.
11. 2. H-Cl is non polar.
31. As you go down the periodic table, the atomic radii increases, thus 1 and 3 are eliminated. And I think as you go down, the metallic properties increases because there are metals at the bottom. Ths the answer I choose is 4.
32. I think this is a typo. S2- should have 8 electrons...I don't know what is the answer then.
33. To find the molecular formula, find the mass of CH2 and then divide it by what you were given for the mass, which is 56 grams. You should get a ratio of 4. Thus muliply the formula by 4. CH2 will become C4H8, which is 3.
34. 4. The atomic number means the number of electrons and protons. P is #15 and S is #16.
35. 3. There is only one Cl atom in all formulas. The mass of Cl is 35.5. Thius, you have to divide the mass of Cl by the mass given. 3 is correct because 35.5/84 is .42. Mulitply that by 100 and you get 42%.
36. 1. M^X with O^2-. You can only have one + for a metal in order to get M2O. Thus, the metal has to be in the first group to have 1+.
37. The answer has to be either 3 or 4. However, 3 is wrong because it is compact, which means it is a solid. Since the question is CO(GAS), the naswer is 4 because gas is free.
38. I forgot how to do this one.
I'm tired. Hope this helps. If you need anything, feel free to message me. I took AP chemistry this year and I did pretty well. Hopefully I did the questions correctly.
Good luck on your test. The AP test for me wasn't that hard. I'm taking my chemistry placement test for college next week online. So thank you for giving me a practice test. =]