Chapter 2: Introductory Chemistry ANATOMY & PHYSIOLOGY Chapter 2: Introductory Chemistry

Concepts of Matter matter - anything that occupies space and has mass - may be changed both physically and chemically physical change - does not alter nature of substance i.e.) change in state - ice to water chemical change - does change composition of substance i.e.) fermentation of grapes

Concepts of Matter states of matter Gas no definite shape; no definite volume. i.e.) air Liquid definite volume; conforms to shape of container i.e.) blood; interstitial fluid Solid – definite shape and volume i.e.) bones d. Plasma

Chemical Reactions energy mass-less; does not take up space measured by its effect on matter ability to do work or to put matter into motion

Chemical Reactions Energy All forms of energy (4) exhibit both: kinetic energy when energy is moving objects; actually doing work - causing an effect potential energy inactive or stored energy

Concepts of Energy 4 forms of energy chemical energy energy stored in the bonds of chemical substances and released when bonds are broken electrical energy energy resulting from movement of charged particles

Concepts of Energy 4 forms of energy radiant energy energy that travels in waves; energy of the electromagnetic spectrum mechanical energy directly involved in putting matter into motion

Concepts of Energy energy form conversion energy is easily converted from one form to another energy conversions are inefficient; some of the initial energy supply is lost (unusable) to the environment as heat

?Question? Is it really lost? If not, where is it? The statement has been made that “some energy is lost in every energy transformation.” Explain the meaning of this statement. Is it really lost? If not, where is it?

Intro to Chemistry Chemical Elements and atoms elements unique substance that cannot be decomposed or broken down into simpler substances by ordinary chemical methods 118 (120) discovered elements; 92 occur naturally; 26 (28) produced artificially 4 different elements make up most of the body

Chemical Elements and atoms four most abundant (making up 96 % of body’s mass) these elements are O,C,H & N elements that make up approx. 3.8 % include Ca, P, K, S, Na, Cl, Mg, Fe trace elements - additional 14 elements present in tiny amounts make up the balance of approx. 0.2% -include: Al, B, Cr, Co, Cu, F, I, Mn, Mo, Se, Si, Sn, V, Zn

Chemical Elements and atoms building block of an element smallest particle that still retains its specific properties two basic parts: nucleus and one or more electrons

Chemical Elements and atoms an atom is a cluster of smaller (subatomic) particles and can be split into these an atom loses the unique properties of its elements when it is split in its subparticles

Atomic Structure subatomic particles three basic particles differing in their: mass, electrical charge, and location within the atom the electrical charge of a particle is a measure of its ability to attract or repel other charged particles

subatomic particles proton – positive charge neutron– neutral charge electron – negative charge

subatomic particles all atoms are electrically neutral; the number of protons must be balanced by the number of its electrons protons and neutrons are clustered at the nucleus

subatomic particles electrons orbit around the nucleus, forming a negatively charged electron cloud most of the volume of an atom is empty space, and nearly all of the mass is concentrated in the nucleus

Differentiating elements/atoms to identify a particular element: atomic number equal to the number of protons its atom contains mass number the sum of the protons and neutrons in its nucleus

Differentiating elements/atoms atoms of different elements are composed of different numbers of subatomic particles again, number of protons and electrons are equal; number of neutrons vary light atoms tend to have equal number of protons, electrons, and neutrons larger atoms have more neutrons than protons and electrons

Differentiating elements/atoms isotopes atoms of almost all elements exhibit two or more structural variations called isotopes isotopes have the same number of protons and electrons, but vary in the number of neutrons they contain - thus, has the same atomic number (same chemical properties) of the element, but has a different atomic mass an element’s lightest isotope is more abundant than its heavier forms

Differentiating elements/atoms radioisotopes heavier isotopes of certain elements are unstable and decompose to become more stable radioactivity – spontaneous atomic decay that involves: ejection of particles alpha (least penetrating) beta electromagnetic energy gamma rays (most penetrating)

?Questions? Why is a study of basic chemistry essential to understanding human physiology? Matter and your body – how are they interrelated? Matter occupies space and has mass. Describe how energy must be described in terms of these two factors.

?Questions? The statement has been made that “some energy is lost in every energy transformation.” Explain the meaning of this statement. (Direct your response to answering the question: Is it really lost? If not, where is it?) According to Greek history, a Greek scientist went running through the streets announcing that he had transformed lead into gold. Both lead and gold are elements. On the basis of what you know about the nature of elements, explain why his rejoicing was short-lived.

?Questions? What four elements make up the bulk of all living matter? (Give both their names and their atomic symbols.) Which of these is found primarily in proteins and nucleic acids? List six other elements found in the body and describe one way in which each is important to body functioning. What is the relationship of an atom to an element?

?Questions? All atoms are neutral. Explain the basis of this fact. Complete this statement: Chemical behavior results from interactions of the ___________ found in the _______________ of the atom.

??Questions?? Define isotope. If an element has three isotopes, which of them (the lightest, the one with an intermediate mass, or the heaviest) is most likely to be a radioisotope? Why? Define radioactivity.