Chapter 2: The Chemistry of Life PT2 Quiz

Acid

PH of 3, orange juice, H+ concentration of 10(-5)

Basic

2:1 ratio of OH- to H+, Soap

Complete the following statements using the words or phrases provided. Each word or phrase may be used more than once or not at all.

A water molecule is composed of (three) atoms The (hydrogen) bonding between water molecules allows water to be cohesive and adhesive Water is (cohesive) (sticks to itself) and (adhesive) )sticks to other substances). Together, these two properties account for water climbing a plant from roots to leaves. Because water is a (polar) molecule, it is a good (solvent) for hydrophilic molecules. Sweating can have a cooling effect, due to (evaporation) this is because energy is needed to break water's (hydrogen) bonds. Frozen water is (less) dense than liquid water, causing ice to float.

Blood is closely maintained at a pH of 7.4. A patient whose blood pH drops below 7.35 is suffering from metabolic acidosis and can go into a coma. What happens to the concentration of H+ ions in a patient with a blood pH of 6.4?

H+ concentration is increased ten fold.

Water molecules exhibit cohesive and adhesive properties. What is the chemical bond characteristics that contributes to these and other numerous important properties of water molecules

Hydrogen bonds form between water molecules, not requiring gain, loss, or sharing of electrons.

Which of the following statements about acids and bases is/are true? (Check all that apply)

If the ratio of protons (H+) to hydroxide ions (OH-) is ten to one (10:1), then the solution is acidic Adding a base to an acidic solution will bring the PH of the solution closer to 7 Acidic compounds are those that release protons (H+) into solution

water has unique properties which include its strength as a solvent; its three environmental stages of solid, liquid, gas; and its temperature regulation. These properties are due to polar covalent bonds between oxygen and hydrogen. The polar covalent bonds are a result of

Oxygen being more electronegative and therefore attracting more electrons than hydrogen

Neutral

Pure water, PH of 7

Algal phytoplankton are single-celled water organisms that perform photosynthesis like plants. In a lake, summer growth of phytoplankton can change the water pH from pH 7.2 to 6.2. Select all of the following that are TRUE about this change

The water pH 6.2 is a stronger acid solution than before the phytoplankton growth. The water at pH 6.2 has 10 times the hydrogen (H+) concentration as before the phytoplankton growth The growth of the phytoplankton changed the pH of the water

How does carbonic acid work to maintain blood pH? (Select all that apply).

When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood. When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood Carbonic acid can raise or lower the pH of blood

The correct functions of your lungs will contribute to the normal pH level between 7.35 and 7.45. If your lungs do not exchange and remove carbon dioxide from your blood, the blood pH will change. A pH 6.4 reading of your blood indicates

a health problem due to 10X higher H+ concentrations than normal in your body

Evaporation of water is a change of water from

a liquid into a vapor

Sugars like glucose (C6H12O6) dissolve well in water because sugars from _____ bonds with water

hydrogen

A base

is a chemical that absorbs hydrogen ions from a solution

An acid

is a chemical that adds hydrogen ions to a solution

Determine which of the following is/ are true about the structure of water ( select all that apply).

water has one oxygen atom and two hydrogen atoms The bonds of a water molecule are polar