Periodic Table and Bonding Test Review (Chapters 12 & 13) KEY 1. There are more than 110 known elements on the Periodic Table, but no element with an atomic number greater than 92 is found naturally in measurable quantities on Earth. The remaining elements are artificially produced in a laboratory setting. 2. What did Rutherford contribute to the Atomic Theory? Most of the atom is empty space (with electrons in the space) AND there is a positive center to the atom 3. What two particles can be found in the nucleus? Protons & Neutrons Each has 1 amu. 4. Isotopes exist because atoms of the same element can have different numbers of neutrons. How do they use the mass of the different isotopes to calculate the atomic mass? It is a weighted average of the masses of the different isotopes of that element (sorta like averaging a grade – some grades are weighted more than others… so some isotopes are found more than others, so those found more in nature are weighted more when they calculate the average) 5. What is the overall charge of an atom? neutral Why? Because they have the same number of protons as electrons before they bond 6. One atom has 17 protons, 18 neutrons, and 17 electrons. Another atom has 17 protons, 19 neutrons and 17 electrons. Are these the same element? Yes No Explain: They both have 17 protons so they are the same element (Chlorine)… they have different numbers of neutrons, so they are isotopes of Chlorine 7. How many valence electrons does an atom of Chlorine contain? 7 How do you know? Because they are in group 17, so 17-10 = 7 valence electrons 8. Calculate the number of protons in an isotope of Zirconium-90, which has an atomic number of 40. No calculation needed – it has 40 (its atomic #!) 9. Calculate the number of neutrons in an isotope of Zirconium-90, which has an atomic number of 40. 90 – 40 = 50 neutrons 10. The Lanthanides and Actinides are all listed at the very bottom of the Periodic Table. Why? Because the periodic table would be too wide if they weren’t Which are radioactive (unstable)? Actinides 11. The most reactive metals are from which Group? Group 1 – Alkali Metals 12. Elements that are mostly non-reactive (also called inert) are from which Group? 18 / Noble Gasses 13. Moseley arranged elements by increasing atomic number but Mendeleev arranged elements by increasing atomic mass. 14. If Fluorine gained a proton, it would be called Neon. If it gained an electron, it would be called a Fluorine ion or F-. 15. Metals tend to give away electrons when bonding, forming positive ions, whereas nonmetals tend to gain electrons when bonding, forming negative ions. 16. Which element is more reactive: Na or K? K (Potassium) Why? The elements become more reactive as you move down the column on the Periodic Table 17. Magnesium is in Period 3. In what energy level will its valence electron(s) be located? 3 What Group number is Magnesium located? 2 What is the name of this Group? Alkaline Earth Metals 18. Li, Sn, Al, and Fe are all metals located to the left of the stair step on the Table. 19. Cl, Ar, He, and N are all nonmetals located to the right of the stair step on the Table. 20. Oxygen, Nitrogen, and Fluorine are all diatomic molecules which are found in nature as two atoms of the element bonded together. 21. An ionic bond is usually between a metal and a nonmetal. 22. What is the total charge of this compound? MgF2? 0 or neutral 23. In covalent bonding electrons are shared while in ionic bonding electrons are transferred / lost or gained. 24. Considering B+3, it has 5 (#) protons, starts with 5 (#) electrons, ( gains / gives away ) 3 (#) electrons, and has 2 (#) electrons based on the charge. 25. Na is a chemical symbol / elements, while NaOH is a chemical formula / compound / bond. 26. The oxidation number for the group of elements in Group 16 on the Periodic Table is 2 meaning that these elements tend to ( gain / lose ) 2 (#) electrons. 27. Covalent bonding occurs between nonmetals and nonmetals and produces a molecule. 28. Al2S3 has both aluminum and sulfur in its composition and therefore has the same properties of both of these elements. ( True / False ) 29. How is the bonding of Cl2 different from the bonding in NaCl? Cl2 is a diatomic / covalent bond whereas NaCl is an ionic bond 30. Explain how Helium can be in Group 18, but doesn’t have 8 valence electrons? Helium only has 2 electrons, so they will fill up the first energy level/shell and therefore it doesn’t want to bond (just like all the other Group 18 Noble Gasses elements) 31. Predict the type of bonding each of the following pairs of atoms would form? a. Zinc and Zinc metallic b. Phosphorus and Oxygen covalent c. Magnesium and Chlorine ionic 32. The energy levels farther from the nucleus contain electrons that have more energy as compared to levels closer to the nucleus. ( less energy / more energy / the same energy ) 33. A molecule is a neutral group of atoms held together by covalent bonds. 34. There are more metals than nonmetals on the Periodic Table. ( true / false )