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Chemistry

The science of the structure and interactions of matter.

Calcium is the most

Important ion in body

Hydrophilic

Interact readily with water

Hydrophobic

Do not interact readily with water

The ph indicates

Hydrogen ion concentration

Matter

Anything that occupies space and has mass.

Mass

The amount of matter a substance contains.

Weight

The force of gravity acting on a mass.

Chemical Symbols

Abbreviations given to chemical elements.

Atoms

Units of matter of all chemical elements, composed of particles.

Protons

Positively charged particles located within the nucleus of an atom.

Neutrons

Uncharged particles located within the nucleus.

Electrons

Negatively charged particles that move about the nucleus in energy levels.

Nucleus

The central part of an atom containing protons and neutrons.

Valence Shell

The outermost shell of an atom that contains its valence electrons.

Atomic Number

The number of protons in the nucleus of an atom.

Electrons are much ____ and orbit around the ___

Lighter / nucleus

Electron cloud

Area around the nucleus that contains electrons

Electron shell

2 dimensional representation of an electron cloud

Element

A pure substance composed of atoms one of a kind can’t be broken down to simpler substances

Human body contains how many elements

13 main element 14 trace elements

Principal elements in human body

Oxygen , carbon , hydrogen , nitrogen

Covalent bond

Strong bond created when atoms share electrons

Sharing 2 , 1, , 3 pairs of electrons

Single covalent bond , double covalent bond , triple covalent bond

Liquid , solid , gas

Constant volume and shape / has volume no shape / and gas has neither

Work

The movement of an object or a change in the physical structure of matter

Energy

The capacity to do work

Types of chemical reactions include

Decomposition , synthesis, exchange , reversible

Solute

The dissolved substance

Solvent

The liquid in which the solutes are distributed

Water is a

Polar molecule

Ion is a

Atom w electric charge

Covalent bonds in 5 common molecules include

Hydrogen, oxygen , carbon dioxide, nitrogen , nitric oxide

Properties of water are

Universal solvent / reactivity / high heat capacity/ lubricant

Mass Number

The total number of protons and neutrons in an atom.

Isotopes

Different atoms of an element that have the same number of protons but different numbers of neutrons.

Stable Isotopes

Isotopes that do not change their nuclear structure over time.

Radioactive Isotopes

Isotopes that are unstable because their nuclei decay.

Dalton

A standard unit for measuring the mass of atoms and subatomic particles.

Ions

Atoms that have lost or gained electrons, resulting in a positive or negative charge.

Molecules

Combinations of two or more atoms that share electrons.

Free Radicals

Electrically charged atoms or groups of atoms with an unpaired electron.

Compounds

Substances that can be broken down into two or more different elements by chemical means.

Chemical Bonds

Forces of attraction that hold the atoms of a molecule together.

Valence Electrons

Electrons in the outermost shell of an atom which determine bonding behavior.

Octet Rule

Atoms will gain, lose, or share electrons to achieve a full outer shell of eight electrons.

Ionic Bonds

Bonds formed by the attraction between positively and negatively charged ions.

Cations

Positively charged ions that have lost one or more electrons.

Anions

Negatively charged ions that have gained one or more electrons.

Electrolytes

Ionic compounds that dissociate into positive and negative ions in solution.

Covalent Bonds

Bonds formed by sharing pairs of valence electrons between atoms.

Polar Covalent Bonds

Bonds where electrons are shared unequally between atoms.

Nonpolar Covalent Bonds

Bonds where electrons are shared equally between atoms.

Hydrogen Bonds

Weak bonds that form when a hydrogen atom is attracted to another atom, usually nitrogen or oxygen.

Chemical Reaction

Occurs when new bonds are formed or old bonds break between atoms.

Reactants

Starting substances of a chemical reaction.

Products

Ending substances of a chemical reaction.

Metabolism

All the chemical reactions occurring in an organism.

Kinetic Energy

Energy associated with matter in motion.

Potential Energy

Energy stored by matter due to its position or state.

Exergonic Reaction

A chemical reaction that releases energy, usually in the form of heat.

Endergonic Reaction

A chemical reaction that requires energy input to occur.

Catalysts

Chemical compounds that speed up reactions by lowering activation energy.

Synthesis Reactions

Reactions where two or more substances combine to form a larger molecule.

Decomposition Reactions

Reactions where a molecule is broken down into smaller parts.

Buffer Systems

Systems that help maintain pH balance in the body.

Acids

Substances that ionize in water to produce hydrogen ions.

Bases

Substances that accept protons or produce hydroxide ions in solution.

pH Scale

A scale that indicates the acidity or alkalinity of a solution.

Hydrolysis

Breaking down larger molecules into simpler ones by adding water.

Dehydration Synthesis

Joining two simple molecules while removing water.

Lipids

Organic compounds that are largely hydrophobic and include fats and oils.

Proteins

Macromolecules that provide structure, regulate processes, and serve as catalysts.

Nucleic Acids

Large organic molecules that carry genetic information.

Adenosine Triphosphate (ATP)

The principal energy-storing molecule in the body.

Acids

Substances that ionize in water to produce hydrogen ions.

Bases

Substances that accept protons or produce hydroxide ions in solution.

pH Scale

A scale that indicates the acidity or alkalinity of a solution.

Hydrolysis

Breaking down larger molecules into simpler ones by adding water.

Joining two simple molecules while

Hydrolysis

Breaking down larger molecules into simpler ones by adding water.

Dehydration Synthesis

Joining two simple molecules while removing water.

Lipids

Organic compounds that are largely hydrophobic and include fats and oils.

Proteins

Macromolecules that provide structure, regulate processes, and serve as catalysts.

Nucleic Acids

Large organic molecules that carry genetic information.

Adenosine Tri

The principal energy-storing molecule in the body.

Lipids

Organic compounds that are largely hydrophobic and include fats and oils.

Proteins

Macromolecules that provide structure, regulate processes, and serve as catalysts.

Nucleic Acids

Large organic molecules that carry genetic information.

Adenosine Triphosphate (ATP)

The principal energy-storing molecule in the body.