Holt Chapter 14 Chapter Review

Using Vocabulary 1. The force of attraction that holds two atoms together is a chemical bond.

2. Charged particles that form when atoms transfer electrons are ions.

3. The force of attraction between the nuclei of atoms and shared electrons is a covalent bond.

4. Electrons free to move throughout a material are associated with a metallic bond.

Shared electrons are associated with a covalent bond.

Understanding Concepts 6. Which element has a full outermost energy level containing only 2 electrons? a) oxygen b) hydrogen c) fluorine d) helium Answer: d) Helium

7. Which (of the following) describes what happens when an atom becomes an ion with a 2- charge? Answer: c) the atom gains 2 electrons

8. The properties of ductility and malleability are associated with which type of bonds? a) ionic b) covalent c) metallic d) none of the above Answer: c) metallic

9. In which area of the periodic table do you find elements whose atoms easily gain electrons? Answer: c) on the right side

10. What type of element tends to lose electrons when it forms bonds? A) metal b) metalloid c) nonmetal d) noble gas Answer: a) metals

11. Which pair of atoms can form an ionic bond? Answer: b) potassium (K) and fluorine (F)

Short Answers 12. List two properties of covalent compounds. Answers could include: - a low melting point, - a low boiling point, - brittle when solid at room temp.

13. Explain why an iron ion is attracted to a sulfide ion but NOT to a zinc ion? Answer: iron and zinc are metals that tend to lose electrons, thus becoming positively charged. They would repel each other. Sulfide ion is negatively charge sulfur atom that gained electron, so is attracted to a positively charge atom such as iron

14. Using knowledge of valence electrons, explain why carbon is an element in so many different molecules. Carbon has 4 valence electrons, therefore can have 4 bonds, including other carbon atoms. This is the most bonding possibilities. Usually atoms with less than 4 valence electrons give up electrons, and may only have one bond.

15. Three types of bonds: Ionic - lose/gain electrons Covalent - share electrons Metallic - electrons can move between ions within a metal

Concept map 16. This was put on the board

Critical Thinking 17. Types of bonding of these pairs: A) zinc + zinc = metallic B) oxygen + nitrogen = covalent C) phosphorus and oxygen = covalent D) magnesium and chlorine = ionic

18. Dots & bonds A) sulfur (S); 6 dots, 2 bonds B) nitrogen (N); 5 dots, 3 C) neon (Ne); 8 dots, 0 bonds D) iodine (I); 7 dots, 1 bond E) silicon (Si); 4 dots, 4 bonds

19. What type of bond does the picture of a hammer is hitting a white, solid object with little parts appearing on the table represent.? Answer: The substance is brittle, and is breaking into tiny pieces, therefore is an ionic bond.

Math in Science 20.Electrons gained/loss and charge Answers: A) calcium (Ca); lose 2 e-; 2 + B) phosphorus (P); gain 3e-; 3 - C) bromine (Br); gain 1e-; 1- D) sulfur (S); gain 2e-; 2 -

Interpreting Graphics 21. The metal band near the eraser is the part of the pencil where metallic bonds are formed.

22. Molecules with covalent bonds in a pencil include: - graphite - wood - eraser

23. Two differences between the properties of the parts of the pencil are: Answer: The metallically bonded part of the pencil is shiny, can be bent without breaking, and is hard in texture; The covalently bonded parts are not shiny, will break when bent, and are softer. Example: eraser, graphite, wood

The End