4. How much heat does it take to melt 5.0 g of ice? 5. How many grams of water can 10. kj boil into vapor?

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1 REFERENCE TABLE REVIEW Since reference table are used so often by scientists and students of science, it is appropriate that high school chemistry students be familiar with them. The tables provided by the New York State Education Department for students taking the Regents Examination are presented here. A brief description of the type of information to be found and some test items based on each of the tables are also provided. However, students are urged to peruse the entire booklet of reference tables thoroughly while taking the examination. There is much additional information to be found in many of the tables. For example, tables may contain definitions, sample equations, the names and the formulas of ions and compounds, etc. Some Regents test items contain phrases such as: "according to Reference Table G...," or "based on Reference Table N" Many other items require information contained in the tables. Students should be aware of this. Competency in information retrieval is one of the important objectives of the chemistry program. TABLE A Standard Temperature and Pressure These are values used as standard condition for gases. They are useful in gas law problems. Always use the temperature in kelvins (see Table T) when used in gas law problems. STP means at conditions of standard temperature and pressure. 1. At constant temperature what is the volume of a gas at 150 kpa pressure if it was 2.50 L at standard pressure? TABLE B Physical Constants for Water Heat of fusion is the amount of heat it takes to melt one gram of ice. The same amount of heat is released when it freezes (heat of solidification). The heat of vaporization is the amount of heat needed to boil one gram of water into gas at its boiling point. The same amount of heat is released as it condenses (heat of condensation). The specific heat capacity is the amount of heat it takes to raise one gram of liquid water one degree Celsius (see Table T). Notice that a change of temperature of one degree Celsius is the same temperature change as one Kelvin. 4. How much heat does it take to melt 5.0 g of ice? 5. How many grams of water can 10. kj boil into vapor? 6. How much heat does it take to heat 5.0 g of water from 15.0 C to 28.0 C? TABLE C Selected prefixes The prefixes and symbols are listed for exponential factors indicating the size of the quantity measured x 10-6 Joules is how many microjoules? kl is how many liters? 2. What is the pressure of 45.0 ml of a gas at 25 C if it had been 1.58 atm at 52 C in 37.0 ml? 3. What is the volume of oxygen gas at STP if it is 56.0 ml at 52 C and 1.58 atm? 9. How many centimeters is 45 km? TABLE D Selected Units This table gives the unit and symbol for important quantities used in chemistry. The units listed are standard international units. 10. What is the standard international unit for heat?

2 11. L is the symbol used for what unit? 12. What is the name and symbol for the standard international unit for pressure? TABLE E Selected Polyatomic Ions Table E has may applications in naming compounds and writing their formulas. Since the charge on each ion is presented, the table is also helpful in determining oxidation numbers. Notice that the convention in the notation for ionic charge is as follows: 1. When the charge is 1 + or 1-, only the sign is given, not the numeral. 2. For charges greater than one, the numeral is written first, then the charge. For example, 2+ or 3-. Oxidation numbers are generally designated sign first, then numeral. For example, +1, -1, +2, -2, etc. (See Periodic Table of the Elements.) When naming acids of polyatomic ions the rules are: 1. If the name of the polyatomic ion ends in -ite, the name of the acid associated with it ends in - ous. For example, nitrous acid produces nitrite ions. 2. If the name of the ion ends in --ate,the name of the acid ends in -ic. Nitric acid produces nitrate ions. 13. The correct formula for the thiosulfate ion is (1) SO 3 2 (2) SO 4 2 (3) SCN (4) S 2 O Which formula correctly represents mercury (I) chloride? (1) Hg 2 Cl (2) HgC1 2 (3) Hg 2 C1 2 (4) Hg 2 C What is the name of the calcium salt of sulfuric acid? (l)calcium thisulfate (2) calcium sulfate (3) calcium sulfide (4) calcium sulfite 16. What is the correct formula for sodium thiosulfate? (1) Na 2 S 2 O 4 (2) Na 2 SO 3 (3) Na 2 SO 4 (4) Na 2 S 2 O 3 TABLE F Solubility Guidelines Solubility rules allow the prediction of precipitation or dissolving upon mixing of ionic solution at moderate concentrations (about 0.1 M to 1.0 M). If it dissolves it will not precipitate. Match a positive ion with a negative ion to use the table. 17. Which of these compounds will readily dissolve in water? (1) Na 3 PO 4 (2) CaCO 3 (3) PbCl 2 (4) Fe(OH) What will most likely happen upon mixing aqueous solutions of (NH 4 ) 2 S and CaBr 2? (1) no precipitate occurs (2) NH 4 Br precipitates (3) CaS precipitates (4) CaBr 2 precipitates 19. Which will not readily dissolve in.water? (1) AgHCO 3 (2) Ag 2 SO 4 (3) AgNO 3 (4) LiOH TABLE G Solubility curves Each of the curves in this table represents the concentration, in grams of solute per l00 grams water, of saturated solutions at various temperatures. Some helpful hints: 1. Be certain to understand the definition of the y axis. 2. Questions often present names, rather than formulas, of compounds. If this represents a problem, be sure to take advantage of the information found in tables E, F, and S. 3. Note that most solids are more soluble at higher temperatures. 4. The gases in the table, HCl, NH 3 (ammonia), and SO 2 show a decrease in solubility with an increase in temperature. This behavior is typical of gases. 20. According to Reference Table G, approximately how many grams of KClO 3 are needed to saturate 100. grams of H 2 O at 40. C? (1) 6 (2) 16 (3) 38 (4) 47

3 21. How many grams of KNO 3 are needed to saturate 50. grams of water' at 70. C? (1) 30. g (2) 65 g (3) 130.g (4) 160.g 22. Which quantity of salt will form a saturated solution of 100. grams of water at 45 C? (1)30.g of KCl (2)35 g of NH 4 Cl (3)60.g of KNO 3 (4) 1l0.g of NaNO A solution contains 90. grams of KNO 3 in 100 grams of H 2 O at 50. C is considered to be (1) dilute and unsaturated (2) dilute and supersaturated (3) concentrated and unsaturated (4) concentrated and supersaturated 24. A solution contains 14 grams of KCl in 100. grams of water at 40 C. What is the minimum amount of KCl that must be added to make this a saturated solution? (1) 14 g (2) 19 g (3) 25 g (4) 44 g 25. According to Reference Table G, how does a decrease in temperature from 40 C to 20 C affect the solubility of NH 3 and KCl? (1) The solubility of NH 3 decreases, and the solubility of KCl decreases. (2) The solubility of NH 3 decreases, and the solubility of KCl increases. (3) The solubility of NH 3 increases, and the solubility of KCl decreases. (4) The solubility of NH 3 increases, and the solubility of KCl increases. TABLE H Vapor Pressure of Four Liquids The vapor pressure of liquids at a particular temperature is a measure of the strength of the intermolecular forces between their molecules. If the vapor pressure is high, the attraction between molecules must be weak. The molecules can escape the liquid easily to become a gas, and the vapor pressure is higher. Liquids boil when their vapor pressure is equal to (or greater than) the atmospheric pressure around the liquid. 26. What is the boiling point of ethanol at standard pressure? 27. Which of the four liquids on Table H has the strongest intermolecular forces? 28. At what temperature will propanone boil if the atmospheric pressure is 70. kpa? TABLE I Heats of Reaction at kpa and 298K The values for the heats of reaction are for one mole of the compound reacting (or if only elements are reacting, for one mole of the compound being formed as a product) if the equation is balanced for one mole of compound. However, if the equations is balanced with a coefficient of 2 in front of the compound, then the heat of reaction is for two moles of compound reacted or formed. Helpful Hints: 1. Where H is negative, the reaction is exothermic. 2. Where H is positive, the reaction is endothermic. 3. Exothermic reactions add heat to the environment and, therefore, raise the temperature of the reaction medium. Dissolving NaOH in water causes the temperature of the water to rise. 4. Endothermic reactions remove heat from the environment. Dissolving NH 4 CI in water lowers the temperature of the water. 29. The greatest amount of energy would be given up by the complete oxidation of (1) CH 4 (g) (2) C 3 H 8 (g) (3) CH 3 OH (4) C 6 H I2 O 6 (s) 30. When KNO3(s) is dissolved in water, the temperature of the water will (1) increase (2) decrease (3) remain the same 31. How much heat is required to form one mole of NO(g) out of its elements? TABLE J Activity Series An element on the list is more reactive than any element below it. The higher neutral metal elements will be oxidized by metal ions below them. The higher neutral non-metals will be reduced by the non-metal ions below them. In

4 a single replacement reaction, a higher element will replace a lower element in a compound. 32. Will Ba react with Mn 2+? 33. Will Na+ react with Cr? 34. What are the products of the reaction Mg + Co(NO 3 ) 2? TABLE K AND TABLE L Common Acids and Common Bases Acids and bases are electrolytes. The positive ion in acids is H+. The negative ion in bases is OH-. Notice that H 2 O + CO 2 is H 2 CO 3 and H 2 O + NH 3 is NH 4 OH. The bottom two acids (carbonic acid and ethanoic acid) and the bottom base (ammonia) are weak. The others listed are strong. TABLE M Common Acid-Base Indicators Acid-base indicators are organic dyes that are a type of acid or base themselves. They occur in two forms one form (and color) when in an acid and another form (and color) when in a base. The first color mentioned for each indicator corresponds to the lower ph of its range and any lower ph. That is its acid indicating color. The second color mentioned corresponds to the indicator's color at the higher ph given and any ph higher. This is the indicator's base range. At a ph inside an indicator's color range, a mixture of the two forms and colors result. When titrating an acid with a base, one tries to use an indicator that changes color at the ph of the equivalency point. 36. Thymol blue would be yellow in what ph solution? 37. Which indicator would be best for an acidbase titration whose equivalency point is at a ph of 6.5? (1) methyl orange (2) bromthymol blue (3) phenolphthalein (4) thymol blue TABLE N Selected Radioisotopes Table N is designed to be used in calculating rates, times, and/or masses involved during the decay of samples of the isotopes specified in a variety of conditions. Nuclide is a term used to refer to any isotope of an element. The particular isotope is indicated by the mass number, which is written as a superscript to the left of the symbol. 14C is read, "carbon fourteen," and refers to the isotope of carbon containing 8 neutrons. Remember: mass number = protons + neutrons. All isotopes of carbon contain 6 protons. Thus, 14 6 = 8 neutrons. The key to utilizing this chart is the statement: At the conclusion of each half-life, the mass of the sample is half of the mass it had at the beginning of that half -life. 38. What is the number of hours required for potassium-42 to undergo 3 half-iife periods? (1) 6.2 hours (2) 12.4 hours (3)24.8 hours (4) 37.2 hour 39. How many grams of a 32-gram sample of 32 P will remain after 71.5 days? (1) 1 (2) 2 (3) 8 (4)4 TABLE O Symbols Used in Nuclear Chemistry The notation of particles.gives the mass number (protons + neutrons) as the upper number and charge as the lower number. This chart together with Table N can be used to write nuclear equations and determine products. 40. Which two particles have approximately the same mass? (1) neutron and electron (2) neutron and deuteron (3) proton and neutron (4) proton and electron

5 41. Which nuclear emission moving though an electric field would be deflected toward the positive electrode? (1) alpha particle (2) beta particle (3) gamma radiation (4) proton 42. Which particle is electrically neutral? (1) proton (2) positron (3) neutron (4) electron TABLE P Organic Prefixes The prefixes are the organic chemistry way of counting carbon atoms in a chain or branch. They can be used together with Table Q to name all chain hydrocarbons up to 10 carbon atoms long. Table p can also be used with Table R to name many other organic compounds. The prefix for the number of carbon atoms is the beginning part of all organic names of compounds from Table Q and R. TABLE Q Homologous Series of Hydrocarbons Hydrocarbons have only the elements hydrogen and carbon. The alkanes have only single bonds, and their names all end in -ane. The alkenes have a double bond in the chain, and their names all end in -ene. The alkynes have a triple bond in the chain, and their names all end in -yne. All hydrogens bond once, and all carbons bond four times. In graphic structural formulas, the bonds are represented by lines. Single bonds have one line, double bonds have two lines, and triple bonds have three lines. If isomers are possible with a different location of the double or triple bond, the carbons must be numbered Name these hydrocarbons: 43. H C C C H 45. H C C C C C C C H 46. Write the molecular formula for 2-octene. TABLE R Organic Functional Groups The difference in chemical properties between organic compounds is mostly due to their functional group. The rest of all organic molecules is just hydrocarbon chains. In the names, the beginning part is the hydrocarbon part, and the ending is unique for the functional group. All alcohols end in ol. All aldehydes end in al, etc. This is not the case, however, for esters and ethers. With the functional group in the middle, these compounds use both hydrocarbon ends in the name Name these compounds: O 47. H C C C C H H O H 48. H C C C C C H H 44. H C C=C C H Br Br H 49. H C C C C C H

6 50. H C C N H 51. Give the structural formula for ethyl methanoate. TABLE S Properties of Selected Elements This table supplies the names and symbols of all the important elements and several of their physical properties. Often the physical properties can help predict chemical properties as well. For example, if the ionization energy and electronegativity are high, the element attracts electrons strongly. It is likely to form negative ions and be a non-metal. If the ionization energy and electronegativity are low, the element will form a positive ion and be a metal. If the melting and boiling points are high, they must have strong intermolecular forces. The densities of the elements are given at STP so if it is very low, the element is a gas. If the melting point is above room temperature, the element is a solid. If the boiling point is below room temperature, the element is a gas. If room temperature is between the melting and boiling points, the element is a liquid. 53. What element has the highest attraction for electrons in a chemical bond? 54. Which element has the biggest atoms? (1) S (2) Cl (3) K (4) Ca 55. What is the minimum energy needed to remove an electron from a neutral potassium atom? 56. Name two common elements which are liquid at room temperature. TABLE T Important Formulas and Equations These formulas allow one to find the relationship needed to do many calculations without committing the formulas to memory. However, unless a student has practiced using them during the year, the formulas do not always make sense if confronting them for the first time at a test. The combined gas laws can be used to solve volume-temperature, volume-pressure, and temperature-pressure problems also. Just divide out the term that does not change. The temperature must be converted to Kelvins if using the gas laws. The specific heat capacity, heat of vaporization, and heat of fusion for water are given on Table B for doing heat calculations. Percent error is commonly done with laboratory results to find the accuracy of an experiment. The density equation shows how the last column of Table S is determined. 58. A student's experiment shows the volume of 1.00 mol of gas at STP to be 26.3 L. The accepted value is 22.4 L. What is the student's percent error? 59. How many grams of salt must be in 500. g of solution to have a concentration of 100. ppm? 60. What is the pressure of nitrogen gas at 50 C if the pressure is 800. torr at 100 C with constant volume? 61. How much heat is needed to melt 100. g of water ice? 62. What volume of 3.5 M NaOH(aq) is needed to titrate 15 ml of 4.5 M HCI(aq) to the equivalency point? 57. How many meters is the radius of a hydrogen atom?

STUDENT TIPS FOR USING THE CHEMISTRY REFERENCE TABLE

STUDENT TIPS FOR USING THE CHEMISTRY REFERENCE TABLE TABLE A: STANDARD TEMPERATURE AND PRESSURE o This table gives the values for Standard Temp. (in C & K) & Pressure (in kpa & atm). o Standard Temperature