Exam 2: The Chemical Context of Life

A group of molecular biologists is trying to synthesize a new artificial compound to mimic the effects of a known hormone that influences sexual behavior. The biologists have turned to you for advice. Which of the following compounds is most likely to mimic the effects of the hormone?

Measurements show that the pH of a particular lake is 4.0. What is the hydrogen ion concentration of the lake?

What is the pH of a solution with a hydroxyl ion (OH-) concentration of 10-12 M?

An atom with atomic number 12 would have what type of chemical behavior in bonding with other elements?

Which of the following would be regarded as compounds?

Which of the following statements correctly describes any chemical reaction that has reached equilibrium?

Figure 2.3 -Which drawing in Figure 2.3 depicts an atom with a valence of 3?

Oxygen has an atomic number of 8 and a mass number of 16. Thus, what is the atomic mass of an oxygen atom?

Figure 2.3 -Which drawing in Figure 2.3 depicts the electron configuration of an atom capable of forming three covalent bonds with other atoms?

Figure 2.2 -Refer to Figure 2.2 (first three rows of the periodic table). If life arose on a planet where carbon is absent, which element might fill the role of carbon?

Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that

Which one of the atoms shown would be most likely to form a cation with a charge of +1?

Increased atmospheric CO2 concentrations might have what effect on seawater?

Which of the following ionizes completely in solution and is considered to be a strong base (alkali)?

Figure 2.4 -How many electrons does an atom of sulfur have in its valence shell (see Figure 2.4)?

What bonding or interaction is most likely to occur among a broad array of molecules of various types (polar, nonpolar, hydrophilic, hydrophobic)?

What is the pH of a 1-millimolar NaOH solution?

When two atoms are equally electronegative, they will interact to form

How would acidification of seawater affect marine organisms?

Equal volumes (5 mL) of vinegar from a freshly opened bottle are added to each of the following solutions. After complete mixing, which of the mixtures will have the highest pH?