Test One Review
Compounds
A compound consists of two or more elements in a definite ratio salt, NaCl table sugar, C12H22O11 water, H2O
Measured Numbers
A measuring tool is used to determine a quantity such as the length or the mass of an object provides numbers for a measurement called measured numbers
Mixtures
A mixture is a type of matter that consists of two or more substances that are mixed, but not chemically combined two or more substances in different proportions that can be separated by physical methods
Writing Numbers in Scientific Notation
A number written in scientific notation contains a coefficient and a power of ten. coefficient power unit of ten 1.5 × 10^2 m The coefficient is at least 1 but less than 10.
Learning Check
A pepperoni pizza is baked at 455 F. What temperature is needed on the Celsius scale? 235 C
Converting Between F and C
A person with hypothermia has a body temperature of 34.8 C. What is this temperature in F? Step 1 Given 34.8 C Need F Step 2 Write a temperature equation. TF = 1.8TC + 32 A person with hypothermia has a body temperature of 34.8 C. What is this temperature in F? Step 3 Substitute known and calculate. TF = 1.8 (34.8 C) + 32 exact tenths = 62.6 + 32 = 94.6 F and to convert oF to oC
Compounds Contain Elements
"Table salt" is a compound that contains the elements sodium and chlorine. The decomposition of salt, NaCl, produces the elements sodium and chlorine. Elements cannot be broken down further.
Learning Check
. l8. . . . l . . . . l9. . . . l . . . . l10. . cm The length of the line could be reported as (2) 9.03 cm (3) 9.04 cm The estimated digit may be slightly different. Both readings are acceptable.
Calculating Heat Loss
A 225-g sample of hot tea cools from 74.6 °C to 22.4 °C. How much heat, in kilojoules, is lost, assuming that tea has the same specific heat as water? Step 1 Given 225 g tea (water) SH(water) = 4.184 J/g °C 74.6 °C to 22.4 °C Need kilojoules A 225-g sample of hot tea cools from 74.6 °C to 22.4 °C. How much heat, in kilojoules, is lost, assuming that tea has the same specific heat as water? Step 2 Calculate the temperature change. ΔT = 74.6 °C - 22.4 °C = 52.2 °C Step 3 Write the heat equation. q = m × ΔT × SH(water)
Pure Substances: Elements and Compounds
A pure substance is classified as a type of matter with a fixed or definite composition an element that is composed of just one type of atom a compound that is composed of two or more elements chemically combined in the same proportion
Measuring Volume
A volume of 1 L or smaller is common in the laboratory. When a liter is divided into 10 equal parts, each is called a deciliter (dL). 1 L = 10 dL = 1 × 101 dL 1 L = 1000 mL = 1 × 103 mL 1 dL = 100 mL = 1 × 102 mL The cubic centimeter (cm3 or cc) is the volume of a cube with the dimensions 1 cm × 1 cm × 1 cm. A cubic centimeter has the same volume as a milliliter. 1 cm3 = 1 cc = 1 mL
Measuring Length, Equalities
An equality shows the relationship between two units that measure the same quantity. For example, 1 m is the same length as 100 cm. The equality is written as: 1 m = 100 cm = 1 × 102 cm 1 m = 1000 mm = 1 × 103 mm 1 cm = 10 mm = 1 × 101 mm
Elements
Elements are pure substances that contain only one type of material include examples such as copper, Cu lead, Pb aluminum, Al
Energy
Energy is defined as the ability to do work can be classified as either kinetic or potential energy Kinetic energy is the energy of motion. Potential energy is determined by the position of an object or its chemical composition.
Writing Conversion Factors
Equalities between two metric quantities or two U.S. system quantities are obtained by definition, and are not used to determine significant figures 1 m = 1000 mm 1 lb = 16 oz 1 min = 60 sec
Writing Conversion Factors
Equalities written between metric and U.S. system quantities contain one number obtained by measurement and therefore count toward significant figures 1 lb = 453.6 g 1 in = 2.54 cm
Measuring Mass, Equalities
Equalities can be written for mass in the metric (SI) system. When metric equalities are used, 1 gram is the same mass as 1000 mg and 0.001 kg. 1 kg = 1000 g 1 g = 1000 mg 1 mg = 0.001 g 1 mg = 1000 µg
Exact Numbers
Exact numbers are those numbers obtained by counting items definitions that compare two units in the same measuring system Exact numbers are not measured, do not have a limited number of significant figures, and do not affect the number of significant figures in a calculation.
Everyday Scientific Thinking
Experiment 2: Visiting a second friend with a cat causes your eyes to itch and you begin to sneeze again, further supporting your hypothesis. Theory: The experimental results indicate that indeed you are allergic to cats.
Solution
For each of the following, indicate whether the unit describes (1) length, (2) mass, or (3) volume A. A bag of onions has a mass of 2.6 kg. (2) B. A person is 2.0 m tall. (1) C. A medication contains 0.50 g of aspirin. (2) D. A bottle contains 1.5 L of water. (3)
States of Matter - Gases
Gases do not have a definite volume or definite shape contain particles that are far apart, move at high speeds and have little attractions to each other Gases take on the shape and volume of their container.
States of Matter - Liquids
Liquids have a definite volume, but not a definite shape contain particles that move slowly in random directions Liquids maintain their own volume, but take on the shape of their container.
Time
Time is based on an atomic clock and is measured in units of seconds (s) in both the metric and SI systems.
Calculating Specific Heat
To calculate the specific heat (SH) of a substance we measure the heat (q) in joules (J), the mass (m) in grams, and the temperature change, which is written as ΔT.
Representative Elements - Groups and Names
Representative elements include Group 1A (1), called Alkali metals Li, Na, K, Rb, Cs, and Fr Group 2A (2) called Alkaline earth metals Be, Mg, Ca, Sr, Ba, and Ra Groups 3A (13), 4A (14), 5A (15), and 6A (16) Group 7A (17), called Halogens F, Cl, Br, I, and At Group 8A (18), called Noble gases He, Ne, Ar, Kr, Xe, and Rn
Specific Heat
Specific heat is different for different substances is the amount of heat, in joules or calories, needed to change the temperature of 1 g of a substance by 1 ° C in the SI system has units of J/g ° C in the metric system has units of cal/g ° C
Learning Check
State the number of significant figures in each of the following measurements: A. 0.030 m 2 SF B. 4.050 L 4 SF C. 0.0008 g 1 SF D. 2.80 m 3 SF
Temperature
Temperature, a measure of how hot or cold an object feels, is measured on the Celsius (ºC) scale is measured on the Kelvin (K) scale in the SI system is 18 ºC or 64 ºF on this thermometer
The Scientific Method Involves
observations, facts obtained by observing and measuring events in nature. an hypothesis, statement that explains the observations. experiments, procedures that test the hypothesis. a theory, model that describes how observations occur using experimental results.
Reporting Length
To report the length of an object observe the numerical values of the marked lines at the end of the object estimate the last digit by visually dividing the space between the smallest marked lines This estimated number is the final digit that is reported for a measured number. The end of the object is between the 4-cm and 5-cm marks. Estimate that the end is halfway between the 4-cm and 5-cm marks and report the value as 4.5 cm. The metric ruler is marked at every 0.1 cm. You can now estimate that the length is halfway between the 4.5-cm and 4.6-cm marks and report the value as 4.55 cm. The end of the object lines up with the 3-cm mark. Because the divisions are marked in units of 1 cm, the estimated digit appears in the tenths place (0.1 cm).
Conversion Factors with Powers
To square the equality 1 m = 100 cm, we square both the number and the unit on each side. Equality: 1 m = 100 cm Area: (1 m)2 = (100 cm)2 or 1 m2 = (100)2 cm2 Conversion factors:
Writing Conversion Factors
Two Conversion Factors for the Equality 60 min = 1 h Numerator Denominator These conversion factors are read as 60 minutes per hour and 1 hour per 60 minutes. The per means "divide."
Length
Useful relationships between units of length include: 1 m = 1.094 yd 1 m = 39.37 in. 1 m = 100 cm 2.54 cm = 1 in.
Mass
Useful relationships between units of mass include: 1 kg = 1000 g 1 kg = 2.205 lb 453.6 g = 1 lb
Volume
Useful relationships between units of volume include: 1 m3 = 1000 L 1 L = 1000 mL 1 mL = 1 cm3 1 L = 1.057 qt 946.3 mL = 1 qt
Potential or Kinetic Energy?
Water in a reservoir behind a dam has potential energy. When the water is released and flows over the dam, its potential energy is converted to kinetic energy.
Metric Conversion Factors
We can write conversion factors for any metric relationship. Both conversion factors represent the same quantity; one is just the inverse of the other.
Converting Between F and C
We can write equations that relate these two scales, F to its corresponding C. To obtain F from C: and to convert F to C:
Learning Check
What is normal body temperature of 37 oC in kelvins? 310 K Step 1 Given 37 oC Need K Step 2 Write a temperature equation. TK = TC + 273 Step 3 Substitute known and calculate. TK = 37 + 273 = 310 K
Learning Check
What is the specific heat of a metal if 24.8 g of the metal absorbs 275 J of energy and the temperature rises from 20.2 ° C to 24.5 ° C? Step 1 Given 24.8 g, 275 J, ΔT = 4.3 ° C Need J/g ° C Step 2 Write the relationship for specific heat. Step 3 Substitute the given values into equation.
Measuring Mass
When measuring the mass of your body, the mass is measured in kilograms (kg) laboratory samples, mass is reported in grams, milligrams (mg), or micrograms (μg) 1 kg = 1000 g = 1 × 103 g 1 g = 1000 mg = 1 × 103 mg 1 mg = 1000 μg = 1 × 103 μg
Learning Check
Write conversion factors for each pair of units: A. liters and milliliters (1 L = 1000 mL) B. meters and kilometers (1 km = 1000 m)
Learning Check
Write the following number in the correct scientific notation, 0.000 058 g. Step 1 Move the decimal point to obtain a coefficient that is at least 1 but less than 10. 0.000 058 Move the decimal 5 places to the right, to give a coefficient of 5.8. Step 2 Express the number of places moved as a power of 10. Moving the decimal 5 places to the right gives a power of −5. Write the product of the coefficient multiplied by the power of 10 with the unit. 5.8 × 10^−5 g
Continued from last slide
and to convert F to C:
Temperature
A. What is the temperature of freezing water? (2) 0 C B. What is the temperature of boiling water? (3) 373 K C. How many Celsius units are between the boiling and freezing points of water? (1) 100
Learning Check
A. Which answer contains three significant figures? (2) 0.00476 B. All the zeros are significant in (2) 25.300 (3) 2.050 ×10^3 C. The number of significant figures in 5.80 × 10^2 is (3) three
Counting Significant Figures
All nonzero numbers in a measured number are significant. Measurement Number of Significant Figures 38.15 cm 4 5.6 ft 2 65.6 lb 3 122.55 m 5
Learning Check
Indicate the unit that completes each of the following equalities: 1000 m = _____ (2) 1 km 0.01 m = _____ (2) 1 cm
Chemical Changes
Chemical changes take place when the original substance is converted to a new substance with different physical and chemical properties. For example when iron nails corrode in the presence of water, a new substance forms on them, a red-orange powder called rust (Fe2O3).
Chemical Properties
Chemical properties describe the ability of a substance • to interact with other substances • to change into a new substance Cooking sugar at high temperatures changes its chemical properties.
Learning Check
Classify each of the following as a (1) change of state (2) change of shape A. chopping a log into kindling wood (2) B. water boiling in a pot (1) C. ice cream melting (1) D. ice forming in a freezer (1) E. cutting dough into strips (2)
Learning Check
Classify each of the following changes as physical or chemical A. burning a candle chemical B. ice melting on the street physical C. toasting a marshmallow chemical D. cutting a pizza physical E. iron rusting in an old car chemical
Learning Check
Classify each of the following properties as physical or chemical: A. ice melts in the sun physical B. copper is a shiny metal physical C. paper can burn chemical D. a silver knife can tarnish chemical E. a magnet removes iron particles from a mixture physical
Learning Check
Complete each of the following equalities: 1 kg = _____ (3) 1000 g B. 1 mm = _____ (1) 0.001 m
Group Numbers
Group Numbers, written at the top of each vertical column, are written two ways: The letter A is used for the representative elements 1A to 8A and the letter B for the transition elements. The numbers 1-18 are used for the columns from left to right.
Heat and Units of Energy, Joules
Heat is associated with the motion of particles. The faster the particles move, the greater the thermal energy of the substance. The SI unit of energy is the joule (J). 1 kJ = 1000 J
Learning Check
How many calories are obtained from a pat of butter if it provides 150 J of energy when metabolized? Step 1 Given 150 J Need calories Step 2 Write a plan to convert units. State equalities, conversion factors. 1 cal = 4.184 J Step 4 Set up problem and calculate.
Everyday Scientific Thinking
Hypothesis 1: Perhaps you are allergic to cats. Experiment 1: To test your hypothesis, you leave your friend's home. If the itching and sneezing stop, perhaps your hypothesis is correct. If the itching and sneezing do not stop, perhaps you have a cold.
Learning Check
Identify each of the following as a homogeneous or heterogeneous mixture: A. hot fudge sundae heterogeneous mixture B. homogeneous mixture C. homogeneous mixture D. heterogeneous mixture B. baby shampoo C. sugar water D. peach pie
Learning Check
Identify each of the following as a pure substance or a mixture. A. pasta and tomato sauce mixture B. aluminum foil pure substance C. helium pure substance D. air mixture
Learning Check
Identify the energy in each example as (1) potential or (2) kinetic. A. rollerblading (2) kinetic B. a peanut butter and jelly sandwich (1) potential C. mowing the lawn (2) kinetic D. gasoline in the gas tank (1) potential
Learning Check
Identify the measurement that has an SI unit. A. John's height is______. (3) 2.1 m B. The mass of a lemon is _____. (2) 0.145 kg C. The temperature is _____. (2) 255 K
Heterogeneous Mixtures
In a heterogeneous mixture, • the composition varies from one part of the mixture to another • the different parts of the mixture are visible Water and copper form a heterogeneous mixture.
Homogenous Mixtures
In a homogeneous mixture, the composition is uniform throughout the sample the different parts of the mixture are not visible Brass is a homogeneous mixture of copper and zinc atoms.
Significant Figures
In a measured number, the significant figures, (SFs) are all the digits, including the estimated digit. All nonzero numbers are counted as significant figures. Zeros may or may or may not be significant, depending on the position in the number.
Classification of Matter
Matter is anything that has mass and occupies space It makes up all things we use such as, • water • wood • plastic bags We can classify matter according to its composition.
States of Matter - Solids
Matter on earth exists in one of three physical states: solids, liquids, or gases. Solids have a definite shape and definite volume. Amethyst, a solid, is a purple form of quartz, SiO2 In a solid, particles are held together by strong attractive forces are arranged in a rigid manner can only move by vibrating slowly in fixed positions
Metals, Nonmetals, and Metalloids
Most metals are shiny solids, such as copper (Cu), gold (Au), and silver (Ag). Metals are ductile, can be shaped into wires malleable, can be hammered into a flat sheet good conductors of electricity melted at much higher temperatures than nonmetals solids at room temperature, except for mercury (Hg) Except for aluminum (Al), the elements along the zigzag line are metalloids. Metalloids include B, Si, Ge, As, Sb, Te, Po, and At exhibit some properties typical of metals and some typical of nonmetals are better conductors of heat and electricity than nonmetals, but not as good as metals are semiconductors because they can be modified to function as conductors or insulators
Physical Changes
Physical changes occur when matter undergoes a physical change of state, but its composition remains constant. Water exists in three states, ice, water, and steam. The physical appearance of a substance can also change with a physical change. For example, when dissolving salt in water, the salt crystals are no longer visible but can be re-formed when the water evaporates.
Physical Properties
Physical properties are characteristics observed or measured without changing the identify of a substance shape, physical state, boiling and freezing points, density, and color of that substance For example, a penny is round, has an orange-red color, and has a shiny luster.
Elements
No. Atomic Weight Name Sym. M.P. (°C) B.P. (°C) Density* (g/cm3) Earth crust (%)* Discovery (Year) Group* Electron configuration Ionization energy (eV) 1 1.0079 Hydrogen H -259 -253 0.09 0.14 1776 1 1s1 13.5984 2 4.0026 Helium He -272 -269 0.18 1895 18 1s2 24.5874 3 6.941 Lithium Li 180 1347 0.53 1817 1 [He] 2s1 5.3917 4 9.0122 Beryllium Be 1278 2970 1.85 1797 2 [He] 2s2 9.3227 5 10.811 Boron B 2300 2550 2.34 1808 13 [He] 2s2 2p1 8.298 6 12.0107 Carbon C 3500 4827 2.26 0.094 ancient 14 [He] 2s2 2p2 11.2603 7 14.0067 Nitrogen N -210 -196 1.25 1772 15 [He] 2s2 2p3 14.5341 8 15.9994 Oxygen O -218 -183 1.43 46.71 1774 16 [He] 2s2 2p4 13.6181 9 18.9984 Fluorine F -220 -188 1.7 0.029 1886 17 [He] 2s2 2p5 17.4228 10 20.1797 Neon Ne -249 -246 0.9 1898 18 [He] 2s2 2p6 21.5645 11 22.9897 Sodium Na 98 883 0.97 2.75 1807 1 [Ne] 3s1 5.1391 12 24.305 Magnesium Mg 639 1090 1.74 2.08 1755 2 [Ne] 3s2 7.6462 13 26.9815 Aluminum Al 660 2467 2.7 8.07 1825 13 [Ne] 3s2 3p1 5.9858 14 28.0855 Silicon Si 1410 2355 2.33 27.69 1824 14 [Ne] 3s2 3p2 8.1517 15 30.9738 Phosphorus P 44 280 1.82 0.13 1669 15 [Ne] 3s2 3p3 10.4867 16 32.065 Sulfur S 113 445 2.07 0.052 ancient 16 [Ne] 3s2 3p4 10.36 17 35.453 Chlorine Cl -101 -35 3.21 0.045 1774 17 [Ne] 3s2 3p5 12.9676 18 39.948 Argon Ar -189 -186 1.78 1894 18 [Ne] 3s2 3p6 15.7596 19 39.0983 Potassium K 64 774 0.86 2.58 1807 1 [Ar] 4s1 4.3407 20 40.078 Calcium Ca 839 1484 1.55 3.65 1808 2 [Ar] 4s2 6.1132 21 44.9559 Scandium Sc 1539 2832 2.99 1879 3 [Ar] 3d1 4s2 6.5615 22 47.867 Titanium Ti 1660 3287 4.54 0.62 1791 4 [Ar] 3d2 4s2 6.8281 23 50.9415 Vanadium V 1890 3380 6.11 1830 5 [Ar] 3d3 4s2 6.7462 24 51.9961 Chromium Cr 1857 2672 7.19 0.035 1797 6 [Ar] 3d5 4s1 6.7665 25 54.938 Manganese Mn 1245 1962 7.43 0.09 1774 7 [Ar] 3d5 4s2 7.434 26 55.845 Iron Fe 1535 2750 7.87 5.05 ancient 8 [Ar] 3d6 4s2 7.9024 27 58.9332 Cobalt Co 1495 2870 8.9 1735 9 [Ar] 3d7 4s2 7.881 28 58.6934 Nickel Ni 1453 2732 8.9 0.019 1751 10 [Ar] 3d8 4s2 7.6398 29 63.546 Copper Cu 1083 2567 8.96 ancient 11 [Ar] 3d10 4s1 7.7264 30 65.39 Zinc Zn 420 907 7.13 ancient 12 [Ar] 3d10 4s2 9.3942 31 69.723 Gallium Ga 30 2403 5.91 1875 13 [Ar] 3d10 4s2 4p1 5.9993 32 72.64 Germanium Ge 937 2830 5.32 1886 14 [Ar] 3d10 4s2 4p2 7.8994 33 74.9216 Arsenic As 81 613 5.72 ancient 15 [Ar] 3d10 4s2 4p3 9.7886 34 78.96 Selenium Se 217 685 4.79 1817 16 [Ar] 3d10 4s2 4p4 9.7524 35 79.904 Bromine Br -7 59 3.12 1826 17 [Ar] 3d10 4s2 4p5 11.8138 36 83.8 Krypton Kr -157 -153 3.75 1898 18 [Ar] 3d10 4s2 4p6 13.9996 37 85.4678 Rubidium Rb 39 688 1.63 1861 1 [Kr] 5s1 4.1771 38 87.62 Strontium Sr 769 1384 2.54 1790 2 [Kr] 5s2 5.6949 39 88.9059 Yttrium Y 1523 3337 4.47 1794 3 [Kr] 4d1 5s2 6.2173 40 91.224 Zirconium Zr 1852 4377 6.51 0.025 1789 4 [Kr] 4d2 5s2 6.6339 41 92.9064 Niobium Nb 2468 4927 8.57 1801 5 [Kr] 4d4 5s1 6.7589 42 95.94 Molybdenum Mo 2617 4612 10.22 1781 6 [Kr] 4d5 5s1 7.0924 43 * 98 Technetium Tc 2200 4877 11.5 1937 7 [Kr] 4d5 5s2 7.28 44 101.07 Ruthenium Ru 2250 3900 12.37 1844 8 [Kr] 4d7 5s1 7.3605 45 102.9055 Rhodium Rh 1966 3727 12.41 1803 9 [Kr] 4d8 5s1 7.4589 46 106.42 Palladium Pd 1552 2927 12.02 1803 10 [Kr] 4d10 8.3369 47 107.8682 Silver Ag 962 2212 10.5 ancient 11 [Kr] 4d10 5s1 7.5762 48 112.411 Cadmium Cd 321 765 8.65 1817 12 [Kr] 4d10 5s2 8.9938 49 114.818 Indium In 157 2000 7.31 1863 13 [Kr] 4d10 5s2 5p1 5.7864 50 118.71 Tin Sn 232 2270 7.31 ancient 14 [Kr] 4d10 5s2 5p2 7.3439 51 121.76 Antimony Sb 630 1750 6.68 ancient 15 [Kr] 4d10 5s2 5p3 8.6084 52 127.6 Tellurium Te 449 990 6.24 1783 16 [Kr] 4d10 5s2 5p4 9.0096 53 126.9045 Iodine I 114 184 4.93 1811 17 [Kr] 4d10 5s2 5p5 10.4513 54 131.293 Xenon Xe -112 -108 5.9 1898 18 [Kr] 4d10 5s2 5p6 12.1298 55 132.9055 Cesium Cs 29 678 1.87 1860 1 [Xe] 6s1 3.8939 56 137.327 Barium Ba 725 1140 3.59 0.05 1808 2 [Xe] 6s2 5.2117 57 138.9055 Lanthanum La 920 3469 6.15 1839 3 [Xe] 5d1 6s2 5.5769 58 140.116 Cerium Ce 795 3257 6.77 1803 101 [Xe] 4f1 5d1 6s2 5.5387 59 140.9077 Praseodymium Pr 935 3127 6.77 1885 101 [Xe] 4f3 6s2 5.473 60 144.24 Neodymium Nd 1010 3127 7.01 1885 101 [Xe] 4f4 6s2 5.525 61 * 145 Promethium Pm 1100 3000 7.3 1945 101 [Xe] 4f5 6s2 5.582 62 150.36 Samarium Sm 1072 1900 7.52 1879 101 [Xe] 4f6 6s2 5.6437 63 151.964 Europium Eu 822 1597 5.24 1901 101 [Xe] 4f7 6s2 5.6704 64 157.25 Gadolinium Gd 1311 3233 7.9 1880 101 [Xe] 4f7 5d1 6s2 6.1501 65 158.9253 Terbium Tb 1360 3041 8.23 1843 101 [Xe] 4f9 6s2 5.8638 66 162.5 Dysprosium Dy 1412 2562 8.55 1886 101 [Xe] 4f10 6s2 5.9389 67 164.9303 Holmium Ho 1470 2720 8.8 1867 101 [Xe] 4f11 6s2 6.0215 68 167.259 Erbium Er 1522 2510 9.07 1842 101 [Xe] 4f12 6s2 6.1077 69 168.9342 Thulium Tm 1545 1727 9.32 1879 101 [Xe] 4f13 6s2 6.1843 70 173.04 Ytterbium Yb 824 1466 6.9 1878 101 [Xe] 4f14 6s2 6.2542 71 174.967 Lutetium Lu 1656 3315 9.84 1907 101 [Xe] 4f14 5d1 6s2 5.4259 72 178.49 Hafnium Hf 2150 5400 13.31 1923 4 [Xe] 4f14 5d2 6s2 6.8251 73 180.9479 Tantalum Ta 2996 5425 16.65 1802 5 [Xe] 4f14 5d3 6s2 7.5496 74 183.84 Tungsten W 3410 5660 19.35 1783 6 [Xe] 4f14 5d4 6s2 7.864 75 186.207 Rhenium Re 3180 5627 21.04 1925 7 [Xe] 4f14 5d5 6s2 7.8335 76 190.23 Osmium Os 3045 5027 22.6 1803 8 [Xe] 4f14 5d6 6s2 8.4382 77 192.217 Iridium Ir 2410 4527 22.4 1803 9 [Xe] 4f14 5d7 6s2 8.967 78 195.078 Platinum Pt 1772 3827 21.45 1735 10 [Xe] 4f14 5d9 6s1 8.9587 79 196.9665 Gold Au 1064 2807 19.32 ancient 11 [Xe] 4f14 5d10 6s1 9.2255 80 200.59 Mercury Hg -39 357 13.55 ancient 12 [Xe] 4f14 5d10 6s2 10.4375 81 204.3833 Thallium Tl 303 1457 11.85 1861 13 [Xe] 4f14 5d10 6s2 6p1 6.1082 82 207.2 Lead Pb 327 1740 11.35 ancient 14 [Xe] 4f14 5d10 6s2 6p2 7.4167 83 208.9804 Bismuth Bi 271 1560 9.75 ancient 15 [Xe] 4f14 5d10 6s2 6p3 7.2856 84 * 209 Polonium Po 254 962 9.3 1898 16 [Xe] 4f14 5d10 6s2 6p4 8.417 85 * 210 Astatine At 302 337 1940 17 [Xe] 4f14 5d10 6s2 6p5 9.3 86 * 222 Radon Rn -71 -62 9.73 1900 18 [Xe] 4f14 5d10 6s2 6p6 10.7485 87 * 223 Francium Fr 27 677 1939 1 [Rn] 7s1 4.0727 88 * 226 Radium Ra 700 1737 5.5 1898 2 [Rn] 7s2 5.2784 89 * 227 Actinium Ac 1050 3200 10.07 1899 3 [Rn] 6d1 7s2 5.17 90 232.0381 Thorium Th 1750 4790 11.72 1829 102 [Rn] 6d2 7s2 6.3067 91 231.0359 Protactinium Pa 1568 15.4 1913 102 [Rn] 5f2 6d1 7s2 5.89 92 238.0289 Uranium U 1132 3818 18.95 1789 102 [Rn] 5f3 6d1 7s2 6.1941 93 * 237 Neptunium Np 640 3902 20.2 1940 102 [Rn] 5f4 6d1 7s2 6.2657 94 * 244 Plutonium Pu 640 3235 19.84 1940 102 [Rn] 5f6 7s2 6.0262 95 * 243 Americium Am 994 2607 13.67 1944 102 [Rn] 5f7 7s2 5.9738 96 * 247 Curium Cm 1340 13.5 1944 102 5.9915 97 * 247 Berkelium Bk 986 14.78 1949 102 6.1979 98 * 251 Californium Cf 900 15.1 1950 102 6.2817 99 * 252 Einsteinium Es 860 1952 102 6.42 100 * 257 Fermium Fm 1527 1952 102 6.5 101 * 258 Mendelevium Md 1955 102 6.58 102 * 259 Nobelium No 827 1958 102 6.65 103 * 262 Lawrencium Lr 1627 1961 102 4.9 Abbreviations and Definitions: No. - Atomic Number M.P. - melting point B.P. - boiling point * Density of elements with boiling points below 0°C is given in g/l and in sorted list they are shown before other elements with boling point >0°C. * Earth crust composition average values are from a report by F. W. Clarke and H. S. Washington, 1924. Elemental composition of crustal rocks differ between different localities (see article). * Group: There are only 18 groups in the periodic table that constitute the columns of the table. Lanthanoids and Actinoids are numbered as 101 and 102 to separate them in sorting by group.
Everyday Scientific Thinking
Observation: Upon leaving your friend's home, the itching and sneezing stop. The observation supports your original hypothesis. To confirm, you visit another friend with a cat.
Everyday Scientific Thinking
Observation: Yesterday you went to visit your friend. Soon after you arrived, your eyes began to itch and you started to sneeze. You observed that your friend has a new cat.
Learning Check
On a cold winter day, the temperature is -15 C. What is that temperature in F? 5 degree F
Periods and Groups
On the periodic table elements are arranged according to similar properties in vertical columns called groups periods are horizontal rows of elements Periods 1 contains two elements: H and He Periods 2 and 3 each contain eight elements: Periods 2 - Li, Be, B, C, N, O, F, He Periods 3 - Na, Mg, Al, Si, P, S, Cl, Ar
Scientific Notation
Scientific notation is used to write very large or very small numbers such as the width of a human hair, 0.000 008 m, which is also written as 8 × 10^−6 m the number of hairs on a human scalp,100 000, which is also written as 1 × 10^5 hairs
Learning Check
Select the correct element name for each symbol: A. N (2) nitrogen B. P (2) phosphorus C. Ag (1) silver D. K (2) potassium E. F (1) fluorine
Learning Check
Select the correct scientific notation for each. A. 0.000 008 (Move the decimal 6 places to right.) (2) 8 × 10^−6 B. 72 000 (Move the decimal 4 places to the left.) (1) 7.2 × 10^4
Learning Check
Select the correct symbol for each element: A. calcium (2) Ca B. sulfur (1) S C. iron (3) Fe D. sodium (3) Na E. magnesium (1) Mg
Conversion Factors with Powers
Sometimes we can use a conversion factor that is squared or cubed. Distance = length Area = length × length = length^2 Volume = length × length × length = length^3
Kelvin Temperature Scale
The Kelvin temperature scale has 100 units between freezing and boiling points 100 K = 100 C or 1 K = 1 C adds 273 to the Celsius temperature TK = TC + 273 is based on 0 K (absolute zero), the lowest possible temperature 0 K = -273 C
Heat Equation from Specific Heat
The amount of heat lost or gained by a substance is calculated from the following equation q = m × ΔT × SH where m represents the mass of substance (g) the temperature change is represented by (ΔT) the specific heat, (SH) of the substance is given in units of (J/g ° C)
Learning Check
The normal temperature of a chickadee is 105.8 F. What is that temperature on the Celsius scale? C. 41.0 C Step 1 Given 105.8 F Need C Step 2 Write a temperature equation. The normal temperature of a chickadee is 105.8 F. What is that temperature on the Celsius scale? C. 41.0 C Step 1 Given 105.8 F Need C Step 2 Write a temperature equation.
Writing Numbers in Scientific Notation
The number of spaces moved to obtain a coefficient between 1 and 10 is shown as a power of ten. 52 000. = 5.2 × 10^4 move decimal 4 spaces left 0.003 78 = 3.78 × 10^−3 move decimal 3 spaces right
Scientific Method
The scientific method is a set of general principles that helps to describe how scientists think.
Learning Check
The step in the scientific method that is indicated in each of the following examples is: (1) observation (3) experiment (2) hypothesis (4) theory A. (1) A blender does not work when plugged in. B. (2) The blender motor is broken. C. (2) The plug has malfunctioned. D. (3) The blender does not work when plugged into a different outlet. E. (4) The blender needs repair.
Heat and Units of Energy, Calories
The unit calorie is the amount of energy needed to raise the temperature of 1 g of water by 1 o C. 4.184 Joules (J) = 1 calorie (cal) (exact) 1 kilocalorie (kcal) = 1000 calories (cal)
Zeros, Decimal Numbers
Zeros at the beginning of decimal numbers are not significant. Measurement Number of Significant Figures 0.440 km 3 0.022 g 2 0.00361 lb 3
Zeros, Decimal Numbers
Zeros at the end of decimal numbers are significant. Measurement Number of Significant Figures 50.80 km 4 200. min 3 40.00 g 4
Zeros, Nondecimal Numbers
Zeros at the end of nondecimal numbers are not significant. Measurement Number of Significant Figures 44 000 km 2 810 cm 2 6 150 000 g 3
Zeros Between Digits
Zeros between nonzero digits are significant. Measurement Number of Significant Figures 50.8 mm 3 2001 min 4 0.0702 lb 3 0.40505 m 5
Zeros, Scientific Notation
Zeros in the coefficient of numbers written in scientific notation are significant. Measurement Number of Significant Figures 4.90 × 103 m 3 8.0 × 10-3 kg 2 6.0330 × 10-5 L 5 Keep only the significant zeros when writing numbers in scientific notation. Measurement Scientific Number of Notation Significant Figures 500. g 5.00 × 102 g 3 400 000 m 4 × 105 m 1 0.300 cm 3.00 × 10−1 cm 3