Exam 2: Life, Chemistry, and Water

Lemon juice has a pH of 2.0, therefore, ____.

High levels of carbon dioxide in the atmosphere are causing ____.

Most pH buffers are ____.

The substance H₂O is considered to be ____.

Describe the difference between cohesion and adhesion, and how they, together, allow water to move upward in plants.

Figure 2.1 -Answer the question using the accompanying figure. The atom depicted in this figure can form ____ covalent bonds with another atom.

Molecules such as H-H and O=O are held together by ____.

Which type of chemical linkage is the weakest?

Chemical bonds that are formed when one atom with a partial positive charge (created from unequal sharing of electrons) is electrically attracted to another atom with a partial negative charge (also created from unequal sharing of electrons) are called ____.

Multiple hydrogen bonds together stabilize proteins into a spiral structure called a ____.

Water has an important stabilizing effect on temperature in living organisms and their environments because as water absorbs heat, much of the energy is used to ____ instead of raising the temperature.

The most common isotope of carbon has an atomic number of 6 and a mass number of 12, while the most common isotope of oxygen has an atomic number of 8 and a mass number of 16. A molecule of CO₂made up of these common isotopes has a molecular weight of ____.

Figure 2.3 - Answer the question using the accompanying figure. The molecule shown is held together by ____.

Seawater typically is ____.

A carbon atom with six protons, seven neutrons, and six electrons has a mass number of ____.

Without ____, living organisms would often experience major changes in pH in their cells.

The hydrogen-bond lattice causes water to have an unusually ____ specific heat, an unusually ____ heat of vaporization, and an unusually ____ density in solid form.

Which element is most likely to accept an electron from another atom?

The four elements that make up more than 96.5% of the weight of living organisms are oxygen, carbon, hydrogen, and calcium.

Radioactive ____ is commonly used to treat patients with dangerously overactive thyroid glands.