AP Notes Chapter 1 Matter & Measurement Chemistry is the study of the nature of ______ and its ____________. Matter is anything that has ____ in unit (_) and occupies _____ in unit (_). Matter exists in several different ______ based on the excitation or ____ in unit (_) of the particles. matter interactions g mass space L phases heat J

Elements can be represented by _____, _______, ________ and _______. Matter composed of only one type of _____ is classified as an __________. 114 accepted elements are listed on the periodic table. Names, symbols- some with ______ origins Elements can be represented by _____, _______, ________ and _______. Know your element symbols and names! 1.1Elements & Atoms atom element foreign Names, symbols, diagrams models

An _____ is the smallest particle of an element that retains the ______________________ of that element. Elements with similar _________ are grouped in the periodic table. Characteristics or properties must be definable and even measurable. atom characteristic properties properties

1.2 Compounds and Molecules When two or more different elements combine together a ________ _________ is formed. The composition (kind and number) of a atoms in a compound can be represented by a ________ _______. Compounds may consist of ____ (charged particles) or _________ (discrete units of atoms). chemical compound chemical formula ions molecules

1.3 Physical Properties Physical properties can be observed without changing the ___________ of a substance. Height, weight or mass, size and color are a few physical properties (Table 1.1) _________ properties depend on amounts and _________ properties do not. Composition Extensive Intensive

Temperature Temperature is a measure of the _______ ______ ______ . Different temperature scales, all are talking about the same height of mercury or alcohol. Derive a equation for converting ºF to ºC Kelvin scale is an ________ scale there is no temperature below 0K. Kelvin temperatures = ºC + 273.15 Kelvin temperatures are _______ related to kinetic energy (the motion of particles). average kinetic energy absolute directly

Density Density Ratio of mass to volume D = m in units of g V mL Useful for identifying a compound Useful for predicting weight An ________________ does not depend on what the material is Volume and hence density are temperature dependant Intrinsic property

0ºC = 32ºF 0ºC 32ºF

100ºC = 212ºF 0ºC = 32ºF 0ºC 100ºC 212ºF 32ºF

100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 0ºC 100ºC 212ºF 32ºF

100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 10ºC = 18ºF 5ºC = 9ºF 1ºC = 9ºF 5 0ºC 100ºC 212ºF 32ºF So 5ºC = 1ºF 9

(0,32) = (C1,F1) (100,212) = (C2,F2) ºF ºC

1.4 Physical and Chemical Change Changes in physical properties are called physical changes Changes in reactants to form new products are caused by a chemical change or chemical reaction Chemical properties of materials are observable only through a chemical change and represented in a chemical equation

Scientific Method A way of solving problems Observation- what is seen or measured Hypothesis- educated guess of why things behave the way they do. (possible explanation) Experiment- designed to test hypothesis leads to new observations, and the cycle goes on

After many cycles, a broad, generalizable explanation is developed for why things behave the way they do Theory – is formed to define a WHY Also regular patterns of how things behave the same in different systems emerges Law – is written to explain HOW Laws are summaries of observations

Theories have predictive value. The true test of a theory is if it can predict new behaviors. If the prediction is wrong, the theory must be changed. Theory- why Law - how

Law Observations Theory (Model) Hypothesis Modify Experiment Prediction Law Experiment

1.5 Classifying Matter Kinetic-molecular theory Helps us interpret properties of matter – matter is composed of tiny particles – particles are continuously in motion – in solids they vibrate usually in a regular array – in liquids & gases more free to move Kinetic energy – force of motion of particles

Observing and describing these particles at the Macroscopic level is the world around us Attempting to describe these particles at the Submicroscopic or particulate level requires models that represent what we think the particles look like and act like

Matter Heterogeneous Homogeneous Solution Pure Substance Element Classifying Matter Matter Heterogeneous Homogeneous Solution Pure Substance Element Compound

1.6 Units of Measurement Matter must be explainable to others which means that individuals communicating must agree on type and units of measurement or at least be able to convert measures between each others measure Qualitative – it is blue, (what shade of blue) Quantitative – it is 4 inches, (well how long is an inch) A common system of measure is needed

Metric System Every measurement has two parts Number Scale (unit) SI system (le Systeme International) based on the metric system Prefix + base unit Prefix tells you the power of 10 to multiply by - decimal system -easy conversions

Metric System Base Units - must be definable or derivable Mass - kilogram (kg) Length- meter (m) Time - second (s) Temperature- Kelvin (K) Electric current- ampere (amp, A) Amount of substance- mole (mol)

Base Unit grams, Liters, meters 100 Prefixes giga- G 1,000,000,000 109 mega - M 1,000,000 106 kilo - K 1,000 103 Hecto - H 1,00 102 Deka - D 1,0 101 Base Unit grams, Liters, meters 100 deci- d 0.1 10-1 centi- c 0.01 10-2 milli- m 0.001 10-3 micro- m 0.000001 10-6 nano- n 0.000000001 10-9

Deriving or describing density Deriving the Liter Liter is defined as the volume of 1 dm3 gram is the mass of 1 cm3 of water at 25oC where then 1Kg of water is the mass of 1 L of water. Deriving or describing density Density is the proportional relationship between an objects mass and its volume, D = m/V

Mass and Weight Mass is measure of resistance to change in motion Weight is force of gravity. Sometimes used interchangeably Mass can’t change, weight can

1.7 Using Numerical Information Systematic error is in same direction each time Better precision implies better accuracy You can have precision without accuracy You can’t have accuracy without precision How well is a measure known? Significance

Accuracy vs. Precision

Accuracy Absolute error (AE) = exp - known % Accuracy = 100 - |%AE|

Relative error (RE) = exp - average Precision Relative error (RE) = exp - average % Precision = 100 - |%RE|

Error Error = experimental – accepted

Significant figures Meaningful digits in a MEASUREMENT Exact numbers are counted, have unlimited significant figures If it is measured or estimated, it has sig figs. If not it is exact. All numbers except zero are significant. Some zeros are, some aren’t

Which zeroes count? In between other sig figs does Before the first number doesn’t After the last number counts iff it is after the decimal point the decimal point is written in 3200 2 sig figs 3200. 4 sig figs

Doing the math Multiplication and division, same number of sig figs in answer as the least in the problem Addition and subtraction, same number of decimal places in answer as least in problem.

Using the units to solve problems 1.8 Problem Solving Conversion of a given measurement to a desired quantity by means of mathematical relationship of data Dimensional Analysis Using the units to solve problems

Dimensional Analysis Use conversion factors to change the units 1 foot = 12 inches (equivalence statement) 12 in = 1 = 1 ft. 1 ft. 12 in Every equality gives 2 conversion factors multiply by the one that will give you the correct units in your answer.

How Many Millimeters in 6.78 inches? Given: 6.78 in. Need: millimeters Connections: 2.54 cm = 1 in. 1cm = 10mm

Sample Distance Problems 11 yards = 2 rod 40 rods = 1 furlong 8 furlongs = 1 mile The Kentucky Derby race is 1.25 miles. How long is the race in rods, furlongs, meters, and kilometers? A marathon race is 26 miles, 385 yards. What is this distance in rods, furlongs, meters, and kilometers?

Sample Mass Problem Apothecaries (druggists) use the following set of measures in the English system: 20 grains ap = 1 scruple (exact) 3 scruples = 1 dram ap (exact) 8 dram ap = 1 oz. ap (exact) 1 dram ap = 3.888 g What is the mass of 1 scruple in grams?

How Many Liters in 1.0 Cubic Yard? Volume Problem How Many Liters in 1.0 Cubic Yard? Given: 1 yd3 Need: Liters Connections: 1 yd = 36 in 2.54 cm = 1 in 1 mL = 1 cm3

Sample Speed Problem Science fiction often uses nautical analogies to describe space travel. If the starship U.S.S. Enterprise is traveling at warp factor 1.71, what is its speed in knots? Warp 1.71 = 5.00 times the speed of light speed of light = 3.00 x 108 m/s 1 knot = 2000 yd/h exactly

Sample Problem The speed of light is 3.00 x 108 m/s. How far will a beam of light travel in 1.00 ns?

Density Density Ratio of mass to volume D = m in units of g V mL Useful for identifying a compound Useful for predicting weight An ________________ does not depend on what the material is Volume and hence density are temperature dependant Intrinsic property

Sample Density Problem 1 An empty container weighs 178.3 g. Filled with carbon tetrachloride (density 1.53 g/cm3 ) the container weighs 317.2 g. What is the volume of the container?

Sample Density Problem 2 A 55.0 gal drum weighs 82.0 lbs. when empty. What will the total mass be when filled with ethanol? density 0.789 g/cm3 1 gal = 3.78 L 1 lb = 454 g