- Slides: 25
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? • 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 fo bonds? • 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? • 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. • - a low melting point, • - a low boiling point, • - brittle when solid at room temp.
• 13. Explain why an iron 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. • Sufide 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. The substance is brittle, and is breaking into tiny pieces, therefore is an ionic bond.
Math in Science • • • 20. Electrons gained/loss and charge A) calcium (Ca); lose 2 e-; 2 + B) phosphorus (P); gain 3 e-; 3 C) bromine (Br); gain 1 e-; 1 D) sulfur (S); gain 2 e-; 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. The matalically bonded part of the pencil is shiny, can be bent without breaking, and is hard in texture; and the covalently bonded parts are not shiny, will break when bent, and are softer.