Fall 2015

08 Sep: If SCST needs to be evacuated while we are in class, how will you exit the building and where is the meeting place?

10 Sep: Name the following two substances: NO2 (gas), K2SO4 (solid). How do the arrangements of the particles differ between these two substances due to their phases of matter at room temperature?

15 Sep: How can science and pseudoscience be distinguished from each other? Suggest two principles you could use.

17 Sep: What are the number of protons and electrons in 32-phosphorus and 39-potassium +1 cation?

22 Sep: Fill in the missing isotope: (a) Ar-40 --> beta + ? (b) U-236 --> 2 n+ Te-137 + ?

24 Sep: Which element in the Periodic Table has the smallest atoms (in size)? Support your answer by explaining why.

29 Sep: List two physical properties of ionic compounds and explain them based on the structure of ionic compounds.

01 Oct: Draw the Lewis Structure of H2S. Is it a polar molecule? Explain.

06 Oct: H2S is a gas at room temperature, but H2O is a liquid. Explain.

08 Oct: Which freezes faster - cooler water or warmer water? Explain.

20 Oct: Calculate the number of water molecules in 250mL of water. (Recall the density of water is 1g/mL)

22 Oct: Liquid water can be produced by the reaction of H2 gas and O2 gas. Thermal energy is released in this reaction. Write a balanced chemical equation for this reaction and predict the sign (positive or negative) of DeltaH and DeltaS for this reaction.

27 Oct: Calculate the pH of a 0.01 M solution of HCl. A 0.01 M weak acid has a pH of 4. Explain why this is different from the value you calculated above.

29 Oct: What is the greenhouse effect? (Briefly explain in a few sentences.) Besides CO2, name one other example of a greenhouse gas in our atmosphere.

03 Nov: In the Duracell battery, two half-reactions are: Zn(s) --> Zn2+(aq) + 2 e and 2 MnO2(s) + 2 e -> 2 MnO2(-)(aq). (i) Identify the anode and cathode in the reaction, and (ii) Write the balanced net chemical equation.

05 Nov: Given the line structure of a molecule, write the chemical formula and name the molecule. (In this case it was 3-methylpentane.)

10 Nov: Ethane is a gas but ethanol is a liquid at room temperature. Explain.

12 Nov: Fill in the blanks: (a) Aldehydes can be converted to carboxylic acids via (blank) reactions. (b) Carboxylic acids react with alcohols to form (blank) via (blank) reactions.

17 Nov: (a) What compounds form addition polymers? (b) What compounds form condensation polymers?

24 Nov: What are the two main components in a triglyceride (fat)? What is the difference between trans-fats and cis-fats?

01 Dec: What is the monomer (building block) of a protein called? Draw its generic chemical structure.

08 Dec: What nucleobases (A,G,C,T) pair up in DNA? (What are the pairings?) What forces hold the two DNA strands together in a double helix?