practice_midterm_key

practice_midterm_key - Chem 237 term test #1 version 001...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chem 237 term test #1 version 001 October 14 th , 2009 1. The three-dimensional structure of macromolecules is formed and maintained primarily through noncovalent interactions. Which one of the following is not a noncovalent interaction? A) disulfide bonds B) hydrogen bonds C) hydrophobic interactions D) ionic interactions E) van der Waals interactions 2. The four covalent bonds in methane (CH 4 ) are arranged around carbon to give which one of the following geometries? A) linear B) tetrahedral C) trigonal bipyramidal D) trigonal planar E) trigonal pyramidal 3. The enzyme trypsin catalyzes the cleavage of polymers of L amino acid but it will not catalyze the cleavage of polymers of D amino acids. This is an example of which of the following? A) biological activity. B) chiral activity. C) racemization. D) stereoisomerization. E) stereospecificity. 4. The standard free energy change Gº for a reaction is -46.11 kJ/mol. Which of the following statements is always true? A) The value of the equilibrium constant is less than one. B) The reaction is always spontaneous as written C) The value of K at 25ºC is 1.19 x 10 8 D) The value of K at 25ºC is 8.4 x 10 -7 E) The reaction is exothermic. Page 1 of 9
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chem 237 term test #1 version 001 October 14 th , 2009 5. Enzymes are biological catalysts that enhance the rate of a reaction by: A) decreasing the activation energy. B) decreasing the amount of free energy released. C) increasing the activation energy. D) increasing the amount of free energy released. E) increasing the energy of the transition state. 6. The phosphorylation of glucose, the first step in its metabolism is energetically unfavorable. How, then, do all cells accomplish this process? A) Cells make sure the concentrations are such that the reaction is favorable. B) The reaction is coupled to an energetically favorable reaction. C) The cells use energy from the light it absorbs and couples that to the unfavorable reaction. D) All cells use more than 1 method to accomplish this process. E) None of the above 7. Which of the following best completes this statement? Nonpolar solutes aggregate in aqueous solution … A) because of the strong attractions between nonpolar molecules. B)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/02/2010 for the course CHEM 233 taught by Professor Daub during the Fall '09 term at Waterloo.

Page1 / 9

practice_midterm_key - Chem 237 term test #1 version 001...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online