CHEM 107

§  Matter is anything that takes up space (volume) and weighs something (mass)

§  Pure substance—made up of only one type of substance

o   ONE chemical formula or symbol

§  Element—simplest type of matter

o   Made up of only one type of ATOM

§  Atom—SMALLEST unit of matter

o   Keeps it unique characteristics

§  Compound—PURE substance made of 2 or more elements chemically JOINED together

§  Mixture—COMBINATION of 2 or more substances

o   Can be SEPARATED into its different components

§  Homogeneous mixture—one whose composition is the SAME throughout; homo- means “same”

·       Ex) brass (copper and zinc atoms)

§  Heterogeneous mixture—one whose composition is NOT uniform but VARIES THROUGHOUT

·       Ex) water molecules and copper atoms

§  the periodic table of the elements

o   LISTING of all the elements on earth

o   Many small blocks. Each block:

§  Holds a different element

§  Has a letter or two symbols are derived from the name of the element

§  Have numbers above and below these letters

o   The letter are CHEMICAL SYMBOL

o   the symbols are derived from the name of the element

o   derived from Latin such as Na for sodium and au for gold

§  group—VERTICAL column of elements with similar chemical behaviors

o   each group has a number and letter designation

§  A designations for main-group elements

§  B designations for transition elements

o   Numbers through 1-18

Metals like to give up electrons

§  Period—HORIZONTAL row

o   Numbered from 1 to 7, sections of 6 and 7 set apart at the bottom of the periodic table

o   Aluminum is always a metal

o   Staircase-shaped line which begins at boron separates metals from nonmetals

o   Elements bordered by the line, with the exception of aluminum (Al) are METALLOIDS

§  Several elements are essential for human health

§  Needed largest quantity are CARBON (C), HYDROGEN (H), OXYGEN (O) , and NITROGEN (N), which make up most biological molecules

§  Macronutrients

o   Needed in quantities greater than 100 mg per day

§  Sodium (Na), magnesium (Mg), potassium (K), calcium (Ca), and chlorine (Cl)

o   Micronutrients

§  Needed in quantities less than 100 mg per day

§  Iodine (I), fluorine (F), iron (Fe), zinc (Zn), and other elements

COMPOUND

§  Combine elements in SPECIFIC ratios

§  Chemical formulas—show that water is composed of 2 particles of hydrogen and 1 particle of oxygen, and table salt (NaCl) is composed of 1 sodium and 1 chlorine

o   Helps identify which elements and how many atoms of each element are present in a compound

HOW MATTER CHANGES

§  Physical change—form of the matter is changed but its identity remains the SAME

o   Form of matter CHANGED, identity is SAME

§  Chemical change—change in CHEMICAL IDENTITY of a substance

o   Known as CHEMICAL REACTION

EXAMPLES:

                            Boiling water becomes steam—physical

                            Butter turns rancid—chemical

                            Burning of wood—chemical

                             Mountain snow melting in spring—physical

                             Decay of leaves in winter—chemical

                             Molten iron solidifying to form a nail—physical

§  Chemical equations

o   Shows what happens to the substances involved in a chemical reaction

o   Reactants—CARBON and OXYGEN

o   Product—CARBON DIOXIDE

§  The reaction arrow means “react to form”

o   Ex) carbon and oxygen = carbon dioxide

BALANCING CHEMICAL EQUATIONS

§  Law of conservation of mass

o   Number of atoms must be the same on both sides of the equation or balanced

EXAMPLES IN NOTEBOOK

1.4 math counts

·       Systeme international d’Unites (SI)--  modern day version of the METRIC system

o   Standard unit for MASS is the KILOGRAM (kg)

o   Standard unit for VOLUME is the LITER (L)

o   Standard unti for LENGTH is the METER (m)

·       Change the meaning of the unit BY POWERS OF 10

KNOW TABLE OF PREFIXES ON PAGE 20!!!!!!

·       Quantities that can be related to each other by an equal sign are EQUIVALENT UNITS: 1 dL = 0.1 L

·       Such equivalencies can be used as CONVERSION FACTORS to convert one unit to another using one or more of these factors

o   10 dL/1 L or 1 L/ 10 dL

·       Dimensional analysis—use of converting units to an equivalent unit

o   Determine the units on your final answer

o   Establish the given information

o   Decide how to set up the problem

§  Given unit x desired unit/ given unit

o   Solve

EXAMPLE: convert 12 gallons to 4 quarts!!! (in notes)

·       Significant figures--all digits in a number representing data or results that are known with certainty plus one uncertain digit

o   Measuring matter

o   Be reasonably

o   Nondigital deice, there is some level of uncertainty in the measurement

o   In AN Y measurement, the significant figures are the digit KNOWN with certainty plus one estimated digit

o   In any measurement, all nonzero numbers are considered significant

§  Any NONzero numbers are significant

§  Zeros between nonzero digits are significant

§  Zeros at the end of a number (trailing zeros) are:

·       Significant if the number contains a decimal point

·       Insignicant if there is NO decimal point

§  Zeros to the LEFT/ leading zeros of the first nonzero integer are NOT significant

·       EXACT NUMBERS—used in defined conversion factors and counted items are exact numbers with an infinite number of significant figures

·       SIGNIFICANT if:

o   Not a zero

o   A zero between nonzero digits

o   A zero at the END of a number with a decimal point

·       A zero NOT significant if:

o   At the BEGINNING of a number with a decimal point

o   In a large number without a decimal point

§  CALCULATING NUMBERS AND ROUNDING

o   Math operation can result in numbers that seem more certain than they are

o   Manipulating measurements with arithmetic cannot increase their certainty

o   An answer can be NO more certain than the least certain number in the calculation

§  RULES FOR SIG FIGS IN CALCULATIONS

o   Addition and subtraction—match the LEAST number of decimal places

o   Multiply and divide—match the least number of sig figs

§  ROUNDING

o   BELOW 5 = round down

o   ABOVE 5 = round up

o   If rounding a large number with NO decimal point, substitute zeros for numbers that are not significant

§  SCIENTIFIC NOTATION

o   General form: C x 10^n

§  C = coefficient

§  A number at least 1 but less than 10

§  N = exponent telling us the number of tens places that apply

o   POSITIVE exponent—the actual number is GREATER than 1

o   NEGATIVE exponent—number is BETWEEN 0 and 1

o   Only sig figs are shown in the coefficient

§  For negative sig figs, DIVIDE

o   Ex) 1/10^-2 = 1/10x10 = 0.01

§  4,300 = 4.3 x 1,000 = 4.3 x 10^3

o   Going LEFT means POSITIVE

o   Going RIGHT means NEGATIVE

§  PERCENT

o   Part/whole x 100%

o   Represented by %

§  Matter—takes up space can also be placed on a scale and weighed

§  Mass—measure of the AMOUNT

o   Common unit for mass is GRAM (g)

§  Weight is determined by the PULL OF GRAVITY on the object

o   Force changed depending on location

§  Volume-measure of the SPACE occupied by matter

o   Lab use, graduated cylinder or pipet

o   Clinical use syringes

o   Unit is milliliter (mL)

§  Milliliters = cubic centimeters (cc or cm^3)

§  Density—(d); comparison of a substances mass to its volume

o   MASS/VOLUME

o   One gram of water has a mass of one milliliter so the density of water is 1.00 g/mL

§  Specific gravity—ratio of the density of a sample to the density of water; (sp gr)

  DENSITY OF SAMPLE/DENSITY OF WATER

o   Liquid density often is measured with respect to water

o   Density of water is 1.00 g/mL at 4 deg C and close to that value at body temperature

o   Ratio of 2 densities that have the same unit

o   Refractometer—specific gravity of a liquid can be measured with a simple instrument

§  Temperature—the measure of hotness or coldness

o   Using a THERMOMETER or an electronic temperature probe

o   US uses FAHRENHEIT scale while many use CELSIUS scale

o   The Kelvin is the SI unit for temperature

o   The most straightforward way to compare temperature scales is to compare temperatures that we are most familiar with and observe their values on each scale

§  0 deg C = freezing

§  100 deg C = boiling

o   The Celsius and kelvin scales have degrees of the SAME size, but the two scales are offset by 273 degrees

§  Kevin (K) = Celsius (deg C) + 273

o   One degree on the Celsius scale is equal to 1.8 degrees on the Fahrenheit scale, and the “zero points” are offset by 32 degrees

§  Deg C = (deg F -32 deg F) x 1 C/1.8 F

§  Deg F = (1.8 F/1 C x deg C) + 32 deg F

§  Body temperature

o   Normal: 98.6 deg F or 37.0 deg C

o   Varies from person to person and changes throughout the day

o   Hyperthermia—human body temperature rises above 40.0 C (104 F)

§   can cause convulsion, coma, or permanent brain damage

o   Hypothermia—body temperature DROPS below 35 C (95 F)

§  feels cold, has cold, irregular heartbeat, and slow breathing rate

§  energy—capacity to do WORK or SUPPLY HEAT

o   potential energy—STORED energy

o   kinetic energy—energy of MOTION

o   law of conservation of energy—energy takes various forms, NEVER CREATED OR DESTROYED

o   joule (J)-SI unit for ENERGY

o   calorie—amount of energy required to RAISE the temperature of one gram of water by one degree Celsius

§  1 calorie = 4.184 joules

o   Calorie (Cal)—1000 times larger than a calorie

§  1 Calorie = 1000 calories

§  Heat—kinetic energy             

o   Flows from a warmer body to a colder one

o   Every substance has the ability to absorb or lose heat as the temp changes

§  Specific heat capacity—amount of heat needed to RAISE the temperature of 1 g of that substance by 1 C

o   Heat/grams x delta T

o   Metals have low specific heat values

o   Water has aery high specific heat

§  State of matter—PHYSICAL form in which the matter exists

o   3 most common states of matter:

§  Solid—definite SHAPE and volume

·       ORDERLY arrangement and are tightly packed together and moving only slightly

§  Liquid—definite VOLUME but takes the shape of its container

·       Particles in a liquid are LESS orderly and moving freely

§  Gas—has NO definite shape or volume but EXPANDS to fill the container in which it is placed

·       Accuracy—the degree of agreement between the TRUE and MEASURED value

·       Precision—a measure of the agreement of replicate measurements

·       Deviation—amount of VARIATION present in a set of replicate measurements

·       Error—difference between the true value and OUR ESTIMATION

o   Random

o   Systematic

UNITS AND DOSING

CALCULATING A DOSAGE:

1)      Determine the UNITS for the final answer

2)      Determine the given information

3)      Determine conversion factors to cancel units

4)      Set up the equation with the given information and conversion factors so that all units cancel except the final answer unit