Problem Set #4 (U1, L17-24)

Transcription

1 Name: Block: Date: Problem Set #4 (U1, L17-24) Vocab/Concepts: Fill in the blanks or circle the correct response in brackets. 1. In our model of the atom, electrons are arranged into, which are also known as energy levels. 2. Energy levels that are to the nucleus are lower in energy. 3. Electrons tend to go in to the energy shells first, until they are filled. 4. During a flame test, electrons jump from one energy level to another, causing to be given off. 5. The outermost shell in an atom is called the shell, and electrons in that shell are called electrons. 6. The outermost electrons are most important because. 7. When there are more protons in the nucleus, the outermost electron s attraction to the nucleus is [weaker] [stronger]. 8. When electrons are in higher energy levels, their attraction to the nucleus is [weaker] [stronger]. 9. Elements toward the bottom left corner of the periodic table are called and have a relatively [strong] [weak] hold on their outermost electrons. 10. Elements toward the top right corner of the periodic table are called and have a relatively [strong] [weak] hold on their outermost electrons. 11. is a measure of how strongly an atom attracts electrons in chemical bonds. 12. When atoms of metals and nonmetals get together, the atoms steal electrons from the atoms. They then stick together. This is known as bonding. 13. When an atom has a charge, it is called a(n). 14. When an atom gains one or more electrons, it becomes a(n). 15. When an atom loses one or more electrons, it becomes a(n). 16. In an ionic compound, the total charge must equal. 17. A group of nonmetal atoms that is bonded together to make a single charged particle is called a. 18. When forming ions, atoms tend to end up with valence electrons. This is known as the rule. 19. (Extension - optional) Electron shells can be further divided into, which are labeled s, p, d, or f.

2 Questions/Problems: 20. For each of the elements listed below, give (a) The number of valence electrons. (b) Instructions for it to form an ion that follows the octet rule (e.g. gain two electrons ). (c) The symbol for the ion it will form. The first one has been completed as an example. Element (a) (b) (c) Sr 2 Lose 2 electrons Sr 2+ Na O Br N Ga Mg 21. For each pair of elements, a) Draw Lewis dot representations of each element. Show the transfer of electrons that will occur when these elements react. Use enough atoms of each element to make sure that each atom has a full octet (see example below). b) Give the formula for the compound they will form together. Al and O a) Al Al O O O Al 3+ Al 3+ O 2- O 2- O 2- b) Al 2 O 3 Note: Al 3+ (1s 2 2s 2 2p 6 ) actually has 8 valence electrons in energy level 2, but they are not shown. Ba and Se

3 Na and S Rb and F Ga and Cl

4 22. completion Sr and N 23. Each entry in the chart below represents an ionic compound. The cation (positive ion), anion (negative ion), chemical formula, and name are all listed. Fill in all the missing information in each entry. The first one is already complete as an example. Cation Anion Formula Name Fe 2+ Cl FeCl 2 iron (II) chloride Na + Al 3+ Ca 2+ Br SO 4 2 O 2 AlBr 3 GaAs Li 3 P rubidium telluride aluminum oxide magnesium nitride

5 Cation Anion Formula Name K + Ba 2+ Al 3+ + NH 4 2 CO 3 NO 3 3 PO 4 2 SO 4 NaH 2 PO 4 CaSO 4 Na 2 SiO 3 SrCrO 4 rubidium nitrate indium carbonate sodium cyanide magnesium hydroxide strontium hydrogencarbonate lithium perchlorate The remainder of the problem set is an optional extension. Read U1, Lessons 23 and 24 from the book. Then answer the questions that follow. 24. Why must a Roman numeral be used to indicate the charge on a transition metal ion?

6 Remember, these are optional extension questions. 25. Fill in the chart below. Cation Anion Formula Name Hg 2+ S 2 NiCl 2 CuCO 3 cobalt (II) sulfate chromium (VI) oxide 26. Write the electron configuration for each of the following elements. You may use the noble gas abbreviation if you wish. (a) oxygen: (b) chlorine: (c) silver: 27. Draw a subshell model for vanadium (V), putting all the electrons in their appropriate places.