Campbell Biology: Ninth Edition - Chapter 3: Water and Life Flashcards
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| 507980137 | polar covalent bond | a covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive | |
| 507980138 | polar molecule | a molecule (such as water) with an uneven distribution of charges in different regions of the molecule | |
| 507980139 | cohesion | the linking together of like molecules, often by hydrogen bonds | |
| 507980140 | adhesion | cling of one substance to another, such as water to plant cell walls by means of hydrogen bonds | |
| 507980141 | surface tension | a measure of how difficult it is to stretch or break the surface of a liquid. Water has a high surface tension because of the hydrogen bonding of surface molecules | |
| 507980142 | kinetic energy | the energy associated with the relative motion of objects. Moving matter can perform work by imparting motion to other matter. | |
| 507980143 | heat | the total amount of kinetic energy due to the random motion of atoms or molecules in a body of matter; also called thermal energy. Heat is energy in its most random form. | |
| 507980144 | temperature | a measure of the intensity of heat in degrees, reflecting the average kinetic energy of the molecules | |
| 507980145 | Celsius scale | a temperature scale equal to 5/9 (F-32) that measures the freezing point of water at ) degrees Celsius and the boiling point of water at 100 degrees celsius | |
| 507980146 | calorie (cal) | the amount of heat energy required to raise the temperature of 1 g of water by 1 degree Celsius; also the amount of heat energy that 1 g of water releases when it cools by 1 degree Celsius. The Calorie (with a capital C), usually used to indicate the energy content of food, is a kilocalorie. | |
| 507980147 | kilocalorie (kcal) | a thousand calories; the amount of heat energy required to raise the temperature of 1 kg of water by 1 degree Celsius | |
| 507980148 | joule (J) | a unit of energy; 1 J = 0.239 cal; 1 cal = 4.184 J | |
| 507980149 | specific heat | the amount of heat that must be absorbed of lost for 1 g of a substance to change its temperature by 1 degree Celsius | |
| 507980150 | heat of vaporization | the quantity of heat a liquid must absorb for 1 g of it to be converted from the liquid to the gaseous state | |
| 507980151 | evaporative cooling | the process in which the surface of an object becomes cooler during evaporation, a result of the molecules with the greatest kinetic energy changing from the liquid to the gaseous state. | |
| 507980152 | solution | a liquid that is a homogenous mixture of two or more substances | |
| 507980153 | solvent | the dissolving agent of a solution. Water is the most versatile solvent known | |
| 507980154 | solute | a substance that is dissolved in a solution | |
| 507980155 | aqueous solution | a solution in which water is the solvent | |
| 507980156 | hydration shell | the sphere of the water molecules around a dissolved ion | |
| 507980157 | hydrophilic | having an affinity for water | |
| 507980158 | colloid | a mixture made up of a liquid and particles that (because of their large size) remain suspended rather than dissolved in that liquid | |
| 507980159 | hydrophobic | having no affinity for water; tending to coalesce and form droplets of water | |
| 507980160 | molecular mass | the sum of the masses of all the atoms in a molecule; sometimes called molecular weight | |
| 507980161 | mole (mol) | the number of grams of a substance that equals its molecular weight in daltons and contains Avogadro's number of molecules | |
| 507980162 | molarity | a common measure of solute concentration, referring to the number of moles of solute per liter of solution | |
| 507980163 | hydrogen ion | a single proton with a charge of 1+. The dissociation of a water molecule (H2O) leads to the generation of a hydroxide ion (OH-) and a hydrogen ion (H+); in water, H+ is not found alone but associates with a water molecules to form a hydronium ion | |
| 507980164 | hydroxide ion | a water molecule that has lost a proton; OH- | |
| 507980165 | hydronium ion | a water molecule that has an extra proton bound to it; H3O+, commonly represented as H+ | |
| 507980166 | acid | a substance that increases the hydrogen ion concentration of a solution | |
| 507980167 | base | a substance that reduces the hydrogen ion concentration of a solution | |
| 507980168 | pH | a measure of hydrogen ion concentration equal to -log [H+] and ranging in value from 0 to 14 | |
| 507980169 | buffer | a solution that contains a weak acid and its corresponding base. A buffer minimizes changes in pH when acids or bases are added to the solution | |
| 507980170 | ocean acidification | decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels | |
| 507980171 | acid precipitation | rain, snow, or fog that is more acidic than pH 5.2 |