Chapter 2: Chemistry of Life

Hydronium Ion

H30 +

Equation for Photosynthesis

6CO2 + 12H20 + light

Why does a reduction reactions always accompany an oxidation reaction?

A chemical reactions in which electrons are exchanged between atoms is called an oxidation reduction reaction.

Distinguish between covalent and iconic bonds

A covalent bond is formed when two atoms share electrons. An iconic bond is formed when one atom gives up an electron to another. The positive ion is then attracted to a negative ion to form an iconic bond

Outline a reason why the control of pH is important in living systems

Acidic solutions contain more hydronium ions than hydroxide ions. Basic solutions contain more hydroxide ions than hydronium ions. Buffers are chemicals that neutralize the effects of adding small amounts of either acid or base to a solution

Name and describe the physical properties of the three states of matter

Addition of energy to a substance can cause its state to change from a solid to a liquid and a liquid to a gas.

Describe the arrangement within energy levels of the six electrons of an atom and carbon

Atoms are composed of protons,neutrons, and electrons. Protons and neutrons make up the nucleus of an atom. Electrons move about the nucleus orbitals.

Isotopes

Atoms of the same element that have a different number of neutrons

How are isotopes of the same element alike?

Compounds consist of elements of two or more elements that are joined by chemical bonds in a fixed proportions

What is the relationship between elements and atoms?

Elements are made up of a single kind of atom and cannot be broken down by chemical means into a simpler substances

Describe the effect of an enzyme on the activation energy in a chemical reaction. Enzymes are biological catalysts. Enxplain what they do in the living systems.

Enzymes lower the amount of activation energy necessary for a reaction to begin in living systems.

Identify the properties of water that are important to life to be able to exist

Hydrogen bonding accounts for most of the unique properties of water. The unique properties of water include the ability to dissolve many substances,cohesion and adhesion, the ability to absorb a relatively large amount of energy as heat, the ability to cool surfaces through evaporation, and low density of ice.

Acid

If the number of hydronium ions in a solution is greater than the number of hydroxide ions

What is Matter?

Matter is anything that occupies space and has mass.

How can we predict which elements are reactive under normal conditions and which are unreactive?

Most elements react to form chemical bonds so that their atoms are more stable. An atom achieves stablility when the orbitals that correspond to its highest energy level are filled with maximum number of electrons

Atomic number

Number of protons the atom has

Hydronic Ion

OH - ion

Iconic Bond

Positive and Negative electrical charges attract each other

Products

Produced by chemical reactions

Explain the roles of reactants and products in a chemical reaction.

Reactants are substances the enter chemical reactions Products are substances produced by chemical reactions

Redox reaction

Reactions in which electrons are transferred between atoms known also as oxidation-reduction reactions.

Illustrate the structure of a water molecule by drawing a space-filling molecule.

The two hydrogen atoms and one oxygen atom that make up a water molecule that are arranged to an angle to one another.

Why does pure water have a neutral pH?

Water ionizes into hydronium ions and hydroxide ions

Why is water called a polar molecule?

Water is a polar molecule. The electrons in the molecule are shared unevenly between hydrogen and oxygen. This polarity makes water effective at dissolving other polar substances

Polar

Water is unevenly distribution of charge

Oxidation Reaction

a reactant loses one or more electrons, thus becoming positive in charge

Reduction Reaction

a reactant that gains one or more electrons thus becoming negative in charge

Base

a solution that contains more hydroxide ions

Reversible Reaction

aA +bB -> cC+dD cC +dD-> aA+bB

Enegry

ability to do work

Ion

an atom or molecule with an electrical charge

Cohesive

an attractive force that holds molecules of a single substance together

Buffers

are chemical substances that neutralize small amounts of acid base added to a solution

Compounds

are made up of atoms of two or more elements in a fixed proportion.

Chemical Bonds

are the attractive forces that hold atoms togther

Enzyme

is a protein or RNA molecule that speeds up metabolic reactions without being permanently changed or destroyed

Solute

is a substance dissolved in a solvent

Solvent

is a substance in the solute is dissolved

Covalent Bond

forms when who atoms share one or more pairs of electrons

Solution

is a mixture in which one or more substances uniformly distributed in another substance. Can be mixtures of solids liquids and gases

Orbital

is a three-dimensional region around the nucleus that indicates the probable location of an electron

Adhesion

is an attractive force between two particles of different substances.

Matter

is anything that occupies space and mass

Weight

is defined as the force produced by gravity acting on mass

Saturated Solution

is one in which no more solute can be dissolve

Proton

is positively charged

Hydrogen Bond

is the force between hydrogen molecule with a partial positive charge and a positive or full negative charge.

Mass

is the quantity of matter an object has.

Molecule

is the simplest part of a substance that retains all of the properties of that substance and can exist in a free state.

Electrons

negatively charged

Neutron

no charge

Concentration

of a solution is the amount of solvent dissolved in a fixed amount of the solution.

Chemical Reaction

one or more substances change to produce one or more different substances

Catalsys

reduce the amt of activation energy

Atom

simplest particle of an element that retains all the properties of an element

Aqueous solutions

solutions in which water is the solvent are universally important to living things

Elements

substances that cannot be broken down chemically into simpler kinds of matter

pH scale

tells us how acidic a substance can be; ranges from 0 to 14 ; 0 is the most acidic; 14 is the most basic; 7 is neutral

Metabolisms

term used to describe all the chemical reactions that occur in organisms

Reactants

that enter chemical reactions

Activation Energy

the amt of energy need to start the reaction

Nucleus

the central region, makes up the bulk mass of an atom consists of two kinds of subatomic particles a proton and neutron

Identify the solute and solvent in a hot chocolate solution that is made of chocolate syrup and warm milk.

the solute is chocolate the solvent is milk

Mass Number

total number of protons and neutrons the atom has

Capillarity

which is the attraction between molecules that results in rise of the surface of liquid when in contact with a solid