Chemistry of Life

Energy

Ability to do work

Covalent bond

Forms when two or more atoms share one or more pairs of electrons

Nucleus

Makes up the bulk (main part) of the mass of the atom and consists of two kinds of subatomic particles

Classify each of the following as an element or compound: HCI, CO2, Cl, Li, and H20

HCl: Compound CO2: Compound Cl: Element Li: Element H2O: Compound

Orbital

3-D region around the nucleus that indicates the probable location of an electron

Redox reaction

A chemical reaction involving both reduction and oxidation, which results in changes in oxidation numbers of atoms included in the reaction

Hydroxide ion

A hydroxide ion is a negatively charged ion con- sisting of one oxygen atom and one hydrogen atom, OH-

Reduction reaction

A reactant gains one or more electrons and becomes a negative charge

Oxidation reaction

A reactant loses one or more electrons and becomes positive charged

pH scale

A scale that scientists have developed for comparing the relative concentrations of hydronium ions and hydroxide ions in a solution. It ranges from 0 to 14

Metabolism

All of the chemical reactions that occur in an organism

Ion

An atom or molecule with an electrical charge

Cohesion

An attractive force that holds molecules of a single substance together

What is matter

Anything that has mass and takes up space

Matter

Anything that occupies space and has mass

What is the relationship between elements and atoms

Atoms make up elements

Isotope

Atoms of the same element that have different number of neutrons

Capillarity

Attraction between molecules that results in the rise of the surface of a liquid when in contact with a solid

Adhesion

Attractive force between two particles of different substances

Chemical bond

Attractive forces that hold atoms together

What is the relationship among hydrogen bonds and the forces of cohesions, adhesions, and capillarity

Cohesion: water clings to polar molecules through hydrogen bonding. Water is adhesive to any substance with which it can form hydrogen bonds. Together help water rise through narrow tubes against the force of gravity

Distinguish between covalent and ionic bonds

Covalent bonds: atoms share one or more pairs of electrons. Ionic bonds: when electrons are transferred from one atom to another

Product

Ending substance in a chemical reaction

Mass number

Equal to the total number of protons and neutrons of the atom

Hydrogen bond

Force of attraction between a hydrogen molecule with a partial positive charge and another atom or molecule with a partial or full negative charge

Why does a reduction reaction always accompany an oxidation reaction

Forces in the universe don't act alone. If one atom or molecule is giving electrons, another must be taking (or sharing). They are apart of a redox reaction

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

High specific heat, adhesion, cohesion, surface tension, density, universal solvent, and polarity

Why is water called a polar molecule

Hydrogen and oxygen atoms share electrons to form covalent bonds. They don't share the electrons equally. The oxygen atom has a greater ability to attract electrons to it because it pulls hydrogen's electrons towards it nucleus. Oxygen then has a negative charge while hydrogen has a positive charge. Because of the uneven distribution of charge, water is called a polar molecule

Acid

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

Explain the roles of reactants and products in a chemical reaction

In a chemical reaction, bonds present in the reactants are broken, and the elements are rearranged and new compounds are formed as the products

Describe the effect of an enzyme on the activation energy in a chemical reaction

In living organisms, enzymes act as catalysts. It decreases the activation energy in chemical reactions without being permanently changed or destroyed

Neutron

Inside the nucleus and has no charge

Proton

Inside the nucleus and is positively charged

Enzymes are biological catalysts. Explain what they do in living systems

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

What effect might a molecule that interferes with the action of carbonic anhydrase have on your body

It is made of carbon dioxide and water into carbonic acid and bicarbonate ions. It help transport oxygen molecules from lung to red blood cells. If the molecule interferes with carbonic anhydrase, the level of oxygen in the blood will drop. If you don't get enough oxgen supply to the brain, you may faint, your heart may stop beating, have a seizure, many things

Solution

MIxture in which one or more substances are uniformly distributed in another substance

Compound

Made up of atoms of two or more elements that are chemically bonded in a fixed proportions. Cake would be a compound because all of the ingredients are together to make batter you cannot see the individual components

Electron

Negative charged particles in an atom that has the same number of protons

Given that elements are pure substances, how many types of atoms make up the structure of a single element?

One because if it had more than one then it would be a compound

Chemical reaction

One or more substances changed to produce one or more different substances

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

Our bodies can function when our pH is good. If we have high ph levels then we are most likely to get sick. This is because diseases like cancer like to live in high acidic levels

Mixture

Physical blend of substances that are not chemically bonded

Enzyme

Protein or RNA molecule that speeds up metabolic reactions without being permanently changed or destroyed. Type of catalyst

Catalyst

Reduces the amount of activation energy that is needed for a reaction to take place because it allows the reaction to proceed faster

Molecule

Simplest part of a substance that retain all of the properties of that substance and can exist in a free state

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

Solid: atoms or molecules are more closely linked together than in liquid or gas. Move less rapidly than the particles that make up a liquid or gas. Maintains a fixed volume and shape. Liquid: fixed volume but no shape. Particles move more freely than in a solid. Gas: particles move the most rapidly. Have little to no attraction to each and they fill the volume of the container they occupy. Thermal energy must be added to the substance to cause a substance to change states

Base

Solution in which there are more hydroxide ions than hydronium ions

Saturated solution

Solution where no more solute can dissolve

Aqueous solution

Solutions in which water is the solvent

Reactant

Starting substance in a chemical reaction

Solute

Substance dissolved in the solvent

Solvent

Substance in which the solute is dissolved

Element

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

Electrons

Surrounds the nucleus and is negatively charged

Activation energy

The amount of energy needed to start the reaction

Concentration

The amount of solute dissolved in a fixed amount of the solution. The more solute dissolved, the greater is the concentration of that solution

Ionic bond

The attraction between negative and positive electrical charges

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

The chocolate syrup would be the solute (because it is dissolved) and the warm milk would be the solvent since it dissolves the syrup

Why does pure water have a neutral pH

The concentrations of ions are balanced and it is neither acidic or basic

Buffer

The control of pH in organisms is often accomplished with buffers. They neutralize small amounts of either an acid or a base added to a solution.

Hydronium ion

The ion H3O+, consisting of a protonated water molecule and present in all aqueous acids.

Atomic number

The number of protons in an atom. Appears directly above the chemical symbol of the element. It determines the chemical properties of an element and where it goes in the periodic table.

Atom

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

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

There are two electrons in its first orbital. The second orbital can hold 8 but carbon only has 4 more electrons

How are isotopes of the same element alike

They have the same chemical properties but slightly different masses

Polar

Uneven distribution of charge

Explain why the terms mass and weight should not be used interchangeably

Weight is dependent on gravity and mass is not. Weight is the amount of gravitational pull on an object. That is why your weight changes is different gravity environments. Mass is the amount of matter IN the object

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

What group they are in.If they are closer to the Alkaline metals then they are reactive but if they are closer to the noble gases then they are unreactive

In a reduction reaction, the reduced atom gains one or more electrons. Why is this reaction called a reduction

When you add electrons to an atom, the atom's charge is being reduced and it becomes negatively charged

Why do living things need a constant supply of energy

Without energy, living things shut down, the organs cannot produce the various enzymes and other fluids the body requires to function

Mass

the quantity of matter an object has