5 Written Questions
5 Matching Questions
- Draw functional group structure and give molecular formula for: Carboxyl.
- What is heat of vaporization? How does it relate to evaporative cooling? What affect does it have on living organisms?
- How do acids and bases affect pH?
- What are the molar concentrations of hydrogen and hydroxide ions in one liter of pure water?
- What is the Universal Solvent?
- a H⁺ = 10⁻⁷ and OH⁻ = 10⁻⁷ Equation: [H⁺][ OH⁻] = 10⁻¹⁴ (always = to 14)
- b Carboxyl (-COOH) acidic properties, components of many biologically important molecules; C double bonded to O and single to OH
Ex: Formic acid or acetic acid
- c Heat required to convert 1g of liquid into a gaseous state (high); Evaporative cooling is the warmest molecules of a liquid leave as a gas; allows us to sweat, or release heat so we don't die
- d Acids raise the concentration of H⁺ ions in an aqueous solution (decreases the pH number)
Bases lower the concentration of H⁺ ions (increases the pH number)
- e WATER!
5 Multiple Choice Questions
- 4 and 4
- Special abilities water takes on when combined with itself (only works with large amounts of molecules, not just a single molecule)
- Phosphate (−OPO₃²⁻) (acid: DNA, cell membrane, ATP); P double to O, single to O, 2 O⁻
Ex: glycerol phosphate
- pH is the measurement used to quantify the H⁺ ion concentration in an aqueous (water) solution
- Organic molecules composed solely of Carbon and Hydrogen; Nonpolar covalent bond so they resist/repel water (ex: fat)
5 True/False Questions
Organic molecules must always contain what? → WATER!
What are the different types of isomers (changes) and how are they different? → Hydrophilic - attracted to water; polar or ionic; has charge
Hydrophobic - repels water; nonpolar; no charge
Be able to calculate the molar concentrations of hydrogen and hydroxide ions from a given pH value or vice versa. → H⁺ = 10⁻⁷ and OH⁻ = 10⁻⁷ Equation: [H⁺][ OH⁻] = 10⁻¹⁴ (always = to 14)
Be able to recreate hydrogen bonding in water. →
(see p. 1 slide 4 in ch. 3)
Why is water in the solid phase less dense? How does this support life? → Hydrogen bonds keep the molecules spread out, so they don't pack together, making them less dense.
The floating ice insulates the body of water underneath it; if ice sank, then all the bodies of water would freeze solid, making life unlivable.