PS 100 - Ch. 23

Glucose is ... A. polar and therefore sticky B. non-polar and therefore sticky C. polar and therefore non-sticky D. non-polar and therefore non-sticky E. none of the above

A. polar and therefore sticky

A chemical reaction is pictured below. Which of the answers is the correct chemical formula to represent the reaction? A. 𝐶𝐻4CH4 + 2𝑂22O2 = 𝐶𝑂2CO2 + 2𝐻2𝑂2H2O B. 𝐶𝐻4CH4𝑂4O4 = 𝐶𝑂4CO4𝐻4H4 C. 𝐶𝐻4CH4 + 𝑂4O4 = 𝐶𝑂2CO2 + 𝐻4𝑂2H4O2 D. 𝐶C + 𝐻4H4 + 2𝑂22O2 = 𝐶C + 𝑂2O2 + 2𝐻22H2 + 𝑂2

A. 𝐶𝐻4CH4 + 2𝑂22O2 = 𝐶𝑂2CO2 + 2𝐻2𝑂

In order to fill their orbitals and satisfy the octet rule, non-metals will typically A. attract extra electrons, just like metals do B. attract extra electrons, unlike metals C. get rid of electrons, like metals do D. get rid of electrons, unlike metals E. none of the above

B. attract extra electrons, unlike metals

When some Ca(NO3)2 dissolves in water which picture best represents what the solution looks like? (Note, the balls are not meant to indicate charge or lack of charge.) (See pic) a. b. c.

b.

In carbon tetra-chloride, CCl44, what is true about the charge distribution? Select one: a. The carbon will be more negative than the chlorine. b. The chlorine will be more negative than the carbon. c. The chlorine and carbon would be equally negative. d. The atoms will become positive and negative ions. e. It is impossible to predict how the electrons will distribute themselves in this type of bond.

b. The chlorine will be more negative than the carbon.

Which of the following would best describe the characteristics of covalent materials? Select one: a. A brittle, transparent solid with a very high melting point. b. A shiny, malleable solid with a very high melting point. c. A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature. d. A brittle, opaque solid with a very high melting point. e. A non-conducting solid at room temperature that will conduct if melted or dissolved.

c. A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature.

Which of the following is a true statement about melting and boiling points in materials made of covalent molecules? Select one: a. Molecules that contain double bonds melt and boil at higher temperatures because the bonds are stronger. b. Molecules that contain triple bonds are the most likely to be gases at room temperature. c. Molecules that are polar have lower melting and boiling points than non-polar molecules. d. Hydrogen bonding between molecules increases melting and boiling points. e. Van der Waals (dispersion) forces lower melting and boiling points.

d. Hydrogen bonding between molecules increases melting and boiling points.

What best describes how oxygen molecules would behave if mixed with water? Select one: a. They would dissolve well because they are polar. b. They would dissolve well because they are not polar. c. They would dissolve poorly or not at all because they are polar. d. They would dissolve poorly or not at all because they are not polar. e. They would dissolve well because they are ionic.

d. They would dissolve poorly or not at all because they are not polar.