Chapter 2- Water and Carbon: The Chemical Basis of Life

Chemical evolution

________ was first taken seriously in 1953 when a graduate student named Stanley Miller performed a breakthrough experiment.

Electrons

________ move around atomic nuclei in specific regions called orbitals.

Specific heat

________ is the amount of energy required to raise the temperature of 1 gram of a substance by 1 °C.

Endothermic

________ " (within heating) "because thermal energy is absorbed by the system during the process.

Electronegativity

________ is a property when atoms of different elements form a bond, they may pull shared electrons toward their nuclei with varying lengths.

Molecules

________ or ions that acquire protons during chemical reactions and lower the hydronium ion concentration of water are called bases.

amount of disorder

The ________ in a system (or the surrounding environment) is called entropy.

Electron shells

________ are numbered 1, 2, 3, and so on, to indicate their relative distance from the nucleus.

left

The initial, or reactant, molecules are shown on the ________ and the resulting, or product, molecules are shown on the right.

anions

Negatively charged ions are called ________.

Monomers

________ polymerize through condensation reactions, also known as dehydration reactions.

Solvent

________ is an agent for dissolving or getting substances into solution.

Buffers

________ are important in maintaining relatively constant conditions, or homeostasis, in organisms.

Molarity

________ is the number of moles of the solute present per liter of solution.

Attraction

________ between unlike molecules, in contrast, is called adhesion.

Substances

________ that do not interact with water are said to be hydrophobic.

Cohesion

________: Along the surface, water molecules hydrogen- bond to those next to them and below them, resulting in a net lateral and downward pull that resists the upward pull of adhesion.

polymerization

The process of linking monomers together is called ________.

Reactions

________ tend to be spontaneous if the products hαve lower potential energy thαn the reactants.

Orbitals

________ are grouped into levels called electron shells.

chemical reaction

When a(n) ________ occurs, one substance is combined with others or broken down into another substance.

neutrons

The sum of the protons and ________ in an atom is called its mass number.

nonpolar covalent

A bond that involves equally shared electrons is called a(n) ________ bond.

organic compounds

Many molecules that contain carbon bonded to other elements, such as hydrogen, are called ________.

Elements

________ are defined as substances that consist entirely of a single type of atom.

transformation of water

The ________ vapor to liquid water releases thermal energy to the environment and is exothermic.

Structural formulas

________ indicate which atoms in a molecule are bonded together.

overall pH

Compounds that minimize changes in pH are called buffers because they reduce the impact of adding acids or bases on the ________ of a solution.

Adhesion

________: At the perimeter of the surface, partial positive charges on water molecules adhere to the negative charges on glass, resulting in an upward pull.

nonpolar molecules

The interactions between ________ that result from being brought together in an aqueous solution are called hydrophobic interactions.

Atoms

________ with more than one unpaired electron in the valence shell can also form double bonds or triple bonds.

Surface tension

________ is the cohesive force caused by attraction between the molecules at the surface of a liquid.

number of unpaired electrons

The ________ found in an atoms valence shell is referred to as its valence.

thermal energy

When two objects with different temperatures come into contact, ________ is transferred between them.

Reactions

________ tend to be spontaneous when the product molecules are less ordered thαn the ________ molecules.

chemical reaction

A(n) ________ that involves a transfer of protons is called an acid- base reaction.

Attraction

________ between like molecules is called cohesion.

chemical reactions

Substances that give up protons during ________ and raise the hydronium ion concentration of water are called acids.

Adhesion

At the perimeter of the surface, partial positive charges on water molecules adhere to the negative charges on glass, resulting in an upward pull

Cohesion

Along the surface, water molecules hydrogen-bond to those next to them and below them, resulting in a net lateral and downward pull that resists the upward pull of adhesion

Open system

can exchange energy with environment, can exchange matter with environment

Closed system

can exchange energy with environment, cannot exchange matter with environment

Isolated system

cannot exchange energy with environment, cannot exchange matter with environment