Chemistry 2202 Test PDF

Review sheet Unit 2 Test chem. 2202 1. How many bonding electrons does an atom of magnesium have? (a) 2 (b) 3 (c) 4 (d) 5 2. What substance could be an ionic? Boiling Point Electrical Conductivity as solid or liquid Other Propert...

Review sheet Unit 2 Test chem. 2202 1. How many bonding electrons does an atom of magnesium have? (a) 2 (b) 3 (c) 4 (d) 5 2. What substance could be an ionic? Boiling Point Electrical Conductivity as solid or liquid Other Properties A. 2630°C poor conductor in both states very hard B. 1770°C conductive in liquid state but not solid hard, brittle C. 2220°C conductive in both liquid and solid states hard but malleable D. 35°C poor conductor in both liquid and solid states soft 3. What substance can conduct electricity when dissolved in water? (a) Ba(s) (b) CI4 (c) BaCl2(s) (d) H2CO 4. Why does argon exist as stable, unbonded atoms? 5. What molecule has a linear shape around its central atom? A. CO2 B. CI4 C. H2CO D. C2H2 6. Which molecule possesses a triple covalent bond? A. CO2 B. CI4 C. H2CO D. C2H2 7. What fifth period element has 2 lone pairs and 2 bonding electron in its valence level? (a) O (b) S (c) Se (d) Te 8. What is the shape around the central atom in a molecule of H2CO? 9. Identify the following bonds as ionic, polar covalent, slightly polar covalent or ionic. Use appropriate notation to indicate bond dipoles. (a) K-F (b) Cl-Cl (c) Si-P (d) P-Cl 10. Which compound can dissolve in water? (a) CI4 (b) CO2 (c) NH3 (d) S8 11. Water, H2O, has a considerably higher boiling temperature than hydrogen sulfide, H2S. How can this be explained? 12. What force of attraction is characterized by the formation of temporary dipoles or instantaneous and induced dipoles? 13. What chemical bond arises when two atoms simultaneously attract a pair of valence electrons? 14. What substance will have the highest boiling point? CI4, CuZn, KI, SiS2 15. What describes the bonding in NaCl? 16. What substance will NOT conduct electricity? Ba(l) Ba(s) BaCl2(l) BaCl2(s) 17. What substance will have the strongest London Dispersion forces? CI4 CO2 NH3 S8 18. Which substance exists at room temperature as a solid crystal lattice consisting of uncountable cations and anions? 19. Which substance has the lowest boiling point? A. HBr B. CI4 C. Cu D. SiO2 20. An unknown substance was found to be very hard, had a very high melting point, did not conduct electricity in the solid or molten state and was insoluble in water. What is the identity of the unknown solid substance? Short Answer: Answer ALL questions fully and concisely in the space provided (20 marks) 1. Draw a correct electron dot diagram for CH3COOH(2) 2. Provide a detailed analysis of the intermolecular forces present in each of these substances and predict which of them has the higher boiling point. (4) (a) CH3PH2 and CH3Cl (b) CH3OH and C5H12 3. Complete the following table (8 marks): a) CH3NH2 b) CH3OH Electron dot: Electron Dot: Name the Shape: ___________________________ Name the Shape: ________________________ VSEPR diagram (include bond dipole if polar): VSEPR diagram (include bond dipole if polar): Polarity:_______________ Polarity: _______________ 4. Explain using a theory of metallic bonding why tin strips are malleable. 5. Explain using a theory of ionic bonding why calcium chloride is brittle and shatters under force. 6. Based on a relative force analysis, arrange the following substances in order of decreasing boiling point (highest to lowest) Explain why? Cn (diamond), Mg, C4H10, C4H9OH, C4H8(OH)2, C4H9Br, MgS, CH4 7. Which of the following compounds would be soluble in a solvent such as carbon tetrachloride, CCl4? Explain why?. (a) H20 (b) Br2 (c) CH3OH (d) CH3CH2CH2CH2CH2CH2OH 8. Which substance, either an ionic compound or alloy would you expect to be easily shaped into a nail? Explain your choice? 9. Why are metal excellent conductors of electrical current? Explain. 10. Why ionic compounds are solids at room temperature? Explain. 11. Sketch an electron sea model for the silver (90%) and copper (10%).