STUDENT TIPS FOR USING THE CHEMISTRY REFERENCE TABLE

Transcription

1 STUDENT TIPS FOR USING THE CHEMISTRY REFERENCE TABLE TABLE A: STANDARD TEMPERATURE AND PRESSURE This table gives the values fr Standard Temp. (in C & K) & Pressure (in kpa & atm). Standard Temperature and Pressure (STP) refers t nrmal cnditins in the atmsphere. This value is imprtant because it is used t enable cmparisns/ cnversins t be made between sets f data/data with different units. REFERRED TO IN GASES/GAS LAW PACKET: Use knwn equivalencies at STP given n Table A t CONVERT between units f pressure! (Remember pressure values fr mmhg & trr are NOT given n the ref. table.) Use when ding GAS LAW PROBLEMS. If a gas is said t be at STP, use the given temperature and pressure values listed n Table A as yur values fr temperature & pressure in the gas law prblem. Ex) 1 liter f a gas at STP is cmpressed t 473mL and the temperature decreases t 243K. What is the new pressure f the gas in atm? Many students may read this and think, there is nt enugh inf, BUT, since the questin states that the gas is at STP, yur P1 and T1 values are 1 atm and 273K respectively. (The rest f the questin is dne as a typical gas law prblem, using the cmbined gas law eqn.) TABLE B: PHYSICAL CONSTANTS FOR WATER Heat f Fusin (Hf) refers t the amunt f energy needed t change a substance frm a slid t a liquid (melt a substance). Heat f Vaprizatin (Hv) refers t the amunt f energy needed t change a substance frm a liquid t a gas (vaprize a substance). The Specific Heat Capacity (c) f a substance refers t the amunt f heat needed t raise the temperature f 1g f that substance 1 C. Table B gives yu these energy values fr WATER nly. REFERRED TO IN ENERGY & THERMODYNAMICS PACKET: Refer t values listed n Table B when ding HEAT ENERGY EQUATIONS invlving water! Plug values int apprpriate variable in frmula. Q=mcΔT (C = 4.18J/g C) phases (change in temperature) Q =mhf (Hf = 334J/g) melting/freezing Q=mHv (Hv = 2260J/g) evapratin/cndensatin

2 TABLE C: SELECTED PREFIXES Shws meaning/relatinships between values f different prefixes. REFERRED TO IN ALL PACKETS Useful as a GUIDE FOR CONVERTING frm ne unit t anther if necessary. TABLE D: SELECTED UNITS A key that shws what the units/unit symbls are fr particular quantities. REFERRED TO IN ALL PACKETS Fr example, if yu give an answer fr a pressure value and yu happen t frget what the units are fr pressure, yu can lk up the standard units n this chart.

3 TABLE E: SELECTED POLYATOMIC IONS Plyatmic ins are multiple atms cvalently bnded tgether pssessing an verall charge Table E lists numerus plyatmic ins; including their names, frmulas, and charges. REFERRED TO IN NAMING/BALANCING/REACTION TYPES PACKET Use table as a guide t help yu when NAMING CMPDS that include plyatmic ins. Ex) MgCO3 = Magnesium Carbnate The charge f the in is criss- crssed t write the frmula fr an inic cmpund cntaining a plyatmic in. Ex) Ammnium Sulfite = (NH4) + (SO3) 2- (Criss- crss charges t get frmula) à (NH4)2 SO3 TABLE F: SOLUBILITY GUIDELINES FOR AQUEOUS SOLUTIONS

4 Table F is used t determine if a cmpund is sluble (disslves well) r insluble (des nt disslve) in H2O! REFERRED TO IN SOLUTIONS PACKET: Left side f table à Lists ins that frm SOLUBLE cmpunds! If ins present in the frmula are present in the clumn f sluble ins, and nne f the exceptins are present, the substance is sluble! Right side f table à Lists ins that frm INSOLUBLE cmpunds! If ins present in the frmula are in the clumn f insluble ins, and nne f the exceptins are present, the substance is insluble! Sluble Cmpunds = Electrlytes Insluble Cmpunds = Nnelectrlytes BEWARE OF EXCEPTIONS! TABLE G: SOLUBILITY CURVES

5 Table G is a graph that shws the slubility f numerus slutes and their ability t disslve in 100g f H2O. H2O is the slvent (the substance that des the disslving) Each curve represents the greatest amunt f slute that can disslve at given temperatures! REFERRED TO IN SOLUTIONS PACKET Ex 1) Based n the graph, hw much KNO3 can disslve in 100g f H2O at 20 C? Ex 2) Based n the graph, hw much KNO3 can disslve in 100g f H2O at 40 C? Ex 3) Based n the graph, hw much KNO3 can disslve in 50g f H2O at 60 C? Ex 4) Based n the graph, hw much KCl can disslve in 200g f H2O at 90 C? Ex 5) In 100g f H2O, hw many grams f NH4Cl will precipitate ut f slutin if the temperature decreases frm 80 C t 50 C? Ex 6) In 200g f H2O, hw many grams f NaNO3 will precipitate ut f slutin if the temperature decreases frm 40 C t 10 C? Ex 7) Hw many grams f HCl are needed t saturate 300g f H2O at 40 C Ex 8) Based n Table G, which cmpund s slubility decreases mst rapidly as the temperature increases? Ex 9) 72g f NH4Cl at 90 C represents what type f slutin? Ex 10) 10g f NH3 at 70 C represents what type f slutin? Ex 11) 90g f HCl at 50 C represents what type f slutin?

6 TABLE H: VAPOR PRESSURE OF FOUR LIQUIDS Vapr Pressure can be defined as the pressure that a vapr exerts n the walls f the cntainer it s in. The Table H graph shws the relatinship between the temperature and the vapr pressures f 4 different liquids. REFERRED TO IN GASES/GAS LAW PACKET Shws relatinship btwn. Temperature and (Vapr) Pressure: As temp. increases, vapr pressure increases! (direct relatinship) Relatinship btwn. Vapr Pressure and Intermlecular Frces: Lwest Vapr Pressure = Strngest Intermlecular Frces Highest Vapr Pressure = Weakest Intermlecular Frces Dtted Line: 101.3kPa = Standard Atmspheric Pressure (The amunt f pressure that the atmsphere exerts n the bjects in it. Therefre, when vapr pressure = atmspheric pressure, a substance BOILS!! In ther wrds, the temp. pint at which the curve fr each liquid tuches the dtted line = the Biling Pint f that liquid!! (See abve)

7 TABLE I: HEATS OF REACTION AT 101.3kPa and 298K Heat f Reactin (ΔH): The amunt f heat given ff r absrbed during a chemical reactin. It is the difference in heat cntent/ptential energy between the prducts and the reactants. ΔH = Energy f prducts Energy f reactants Table I lists multiple reactins and gives the ΔH values fr each reactin. REFERRED TO IN KINETICS & EQUILIBRIUM PACKET The ΔH value given fr each reactin allws yu t determine whether each particular reactin is endthermic r exthermic. Negative ΔH value = exthermic (spntaneus) rxn (happen autmatically) Psitive ΔH value = endthermic (nnspntaneus) rxn (have t make them happen) ENDOTHERMIC EXOTHERMIC

8 TABLE J: ACTIVITY SERIES Lists varius metals/nnmetals in rder f reactivity. Metals/Nnmetals at the tp f the chart are mst active. Metals/Nnmetals at the bttm f the chart are least active. REFERRED TO IN REACTIONS, ACIDS, BASES& SALTS, AND REDOX PACKETS Metals abve H2 n Table J WILL react with acids t prduce H2(g) and a salt! Ex1) Mg + 2HCl à MgCl2 + H2 (Rxn. takes place b/c Mg is abve H2 n table) Ex2) Cu + HCl à N Reactin! (b/c Cu is nt abve H2) Table J is als used t predict whether a reactin is spntaneus r nt spntaneus/if a single replacement reactin will take place! RULE: Metals that are mre active (higher n Table J) will REPLACE metals belw them frm cmpunds. In ther wrds, if a metal is higher n Table J than the in r metal in the cmpund, then the reactin WILL ccur (i.e. it is spntaneus) The same rules apply fr nnmetals! Ex1) F2 + 2NaCl à 2NaF + Cl2 (Spntaneus) (Single Replacement takes place) (This is b/c F2 (the nnmetal by itself) is mre active than Cl (the nnmetal in cmpd.) Ex2) Cl2 + 2NaF à N Reactin (Nt Spntaneus) (This is b/c Cl2 is less active than F) Ex3) Ca + MgCO3 à CaCO3 + Mg (Spntaneus) (Single Replacement takes place) (This is b/c Ca (the metal by itself) is mre active than Mg (the metal in cmpd.) Ex 4) Fe 2+ + Cuà N Reactin (Nt Spntaneus) (This is b/c Cu is less active than the in (Fe 2+ )

9 Table J is als used fr electrchemical cell interpretatin. Metals at tp are mst easily xidized Nnmetals at tp are mst easily reduced Metals at bttm are least easily xidized Electrchemical Cell Examples: Nnmetals at bttm are least easily reduced The metals HIGHER n J (Mg/Zn) à mre easily xidized ( AN OX ) SO: these electrdes = ANODES (where xidatin (lss f e - s) takes place) The metals LOWER n Table J (Al/Ag) are therefre the CATHODES ( RED CAT ) (where reductin (gain f electrns) takes place)

10 TABLE K: COMMON ACIDS Table gives list f cmmn acids REFERRED TO IN ACIDS, BASES & SALTS PACKET Use list f given acids as guidelines fr recgnizing the general frmula fr any acid. i.e. Lk fr a H at beginning f frmula, fllwed by ne (r mre) nnmetal(s). Exceptin: Cmpunds that end in COOH (Organic Acids) List f acids can als be used when writing Neutralizatin Reactins. Acid frm Table K + Base frm Table L à Salt + Water Be careful that # f H + = # f OH - TABLE L: COMMON BASES Table gives list f cmmn bases REFERRED TO IN ACIDS, BASES & SALTS PACKET Use list f given bases as guidelines fr recgnizing the general frmula fr any base. i.e. Lk fr a (Metal + OH) Exceptin: Ammnia (NH3) List f bases can als be used when writing Neutralizatin Reactins.

11 TABLE M: COMMON ACID- BASE INDICATORS An indicatr is a dye that changes clr in the presence f an acid r a base This table gives a list f cmmn acid- base indicatrs and gives the gradual clr change that wuld be bserved at an apprximate ph range. REFERRED TO IN ACIDS, BASES & SALTS PACKET Hw t interpret Table M: Ex 1: Means: At a ph f 3.8 r lwer: brmcresl green is yellw At a ph btwn : brmcresl green changes clr frm yellw t blue At ph f 5.4 r higher: brmcresl green is blue

12 TABLE N: SELECTED RADIOISOTOPES Table N gives a list f radiistpes, their half- lives, and their decay mdes. An istpes HALF LIFE refers t the time it takes fr HALF f that sample t DECAY. Ex1) Based n Table N, the half life fr 42 K is 12.4 hurs. - This means that in 12.4 hurs, half f a sample f 42 K will decay. - S: If yu have a 50g sample f 42 K, after 12.4 hurs, nly HALF f it will be left: i.e. 25g In anther hurs, nly 12.5g will be left. In anther hurs, nly 6.25g will be left. Etc etc DECAY MODE refers t the methd by which a particular substance decays. It is dependant upn the type f particle that is given ff as a result f the decay! i.e. alpha decay = alpha particles are emitted as a result f the decay i.e. beta decay = beta particles (electrns) are emitted as a result f the decay i.e. psitrn decay = psitrns are emitted as a result f the decay i.e. gamma decay = gamma rays are emitted as a result f the decay REFERRED TO IN NUCLEAR CHEMISTRY PACKET Used t help slve HALF LIFE PROBLEMS! Many times when slving half life prblems yu will need t lk up the half life f a particular istpe. This table is useful t prvide yu with that reference.

13 TABLE O: SYMBOLS USED IN NUCLEAR CHEMISTRY Table O lists cmmn particles assciated with nuclear chemistry and nuclear reactins. Fr each particle the ntatin indicates the fllwing: Tp # = mass f the particle) Bttm # = charge f the particle Beta Particle Alpha Particle Psitrn Gamma Radiatin Mass: 0 Mass: 4 Mass: 0 Mass: 0 Charge: - 1 Charge: +2 Charge: +1 Charge: 0 The symbl fr each particle is als given. REFERRED TO IN NUCLEAR CHEMISTRY PACKET Used especially when writing/figuring ut decay equatins. When writing decay equatins, always remember: 1. Atmic # n left side f arrw MUST = the sum f the atmic # s n right side f arrw!! 2. Mass # n left side f arrw MUST = the sum f the mass # s n the right side f arrw!! Als Remember: The type f particle emitted = the type f decay TABLE P: ORGANIC PREFIXES Lists the prefixes used in naming rganic cmpunds. REFERRED TO IN ORGANIC CHEMISTRY PACKET Each prefix refers t the # f carbn atms present in the cmpund. Ex1) if the cmpund is Prpane: The cmpund will have 3 carbns Ex2) if the cmpund is Hexyne: The cmpund will have 6 carbns

14 TABLE Q: HOMOLOGOUS SERIES OF HYDROCARBONS Table Q lists the 3 main types f hydrcarbns and gives their general frmulas and structural frmulas Hydrcarbns are rganic cmpunds that nly cntain carbn & hydrgen. REFERRED TO IN ORGANIC CHEMISTRY PACKET This table can be used alngside tables P and R t help name, recgnize, & draw rganic cmpunds. Table Q particularly helps in the naming, drawing, and recgnitin f hydrcarbns and their frmulas. The structural frmulas n the table als indicate the # f bnds between carbn atms f each specific type f hydrcarbn. Ex) alkanes à single bnd btwn carbn atms alkenes à duble bnd btwn carbn atms alkynes à triple bnd btwn carbn atms Use the general frmulas listed as guides t recgnize frmulas fr specific hydrcarbns. (n = # f carbn atms) Ex1) C6H10 à CnH2n- 2 (Therefre frmula fr an alkyne) Ex2) C4H8 à CnH2n (Therefre frmula fr an alkene)

15 TABLE R: ORGANIC FUNCTIONAL GROUPS This table lists 9 ther types f rganic cmpunds that students will need t knw hw t identify, draw, and name. Table R gives the functinal grup, general frmula, and an example fr each family f rganic cmpunds. REFERRED TO IN ORGANIC CHEMISTRY PACKET The functinal grups fr each type f rganic cmpund can be recgnized as ne r mre atms that replace hydrgen in the rganic cmpund, define the structure f the family f cmpunds, and determine the prperties f that family. The general frmulas help yu lcate the placement f the functinal grup in cmparisn t the rest f the frmula. The example clumn serves as a guide fr naming specific cmpunds. Use each clumn simultaneusly when attempting t recgnize, draw and/r name a specific rganic cmpund!

16 TABLE S: PROPERTIES OF SELECTED ELEMENTS

17 This table lists all the names, symbls, densities, biling pints, etc fr all the elements in the peridic table. The table is arranged in rder f increasing atmic number. REFERRED TO IN MATH/LAB SKILLS, PT, BONDING, ENERGY & THERMODYNAMICS PACKETS In PT PACKET, Table S is very useful as a guide t help yu recgnize trends f the peridic table: i.e. what happens t atmic number, inizatin energy, electrnegativity, biling pint, atmic radius, etc.. as yu g dwn a grup r acrss a perid? In MATH/LAB SKILLS PACKET, the densities at STP listed n Table S, alng with the gram frmula mass (nt listed, but must be calculated) fr a particular element, may be used t determine the vlume f a particular element using the density frmula. In ENERGY/THERMODYNAMICS, it gives yu the MP/BP f the substances and therefre what phase f matter it is at STP. In BONDING, the EN f the elements are listed t help determine if a cmpund is inic/cvalent, plar/nn- plar, r t see which is mre r less plar. TABLE T: IMPORTANT FORMULAS AND EQUATIONS DENISTY FORMULA: (Math & Lab Skills) MASSà MOLE CONVERSION FORMULA: (Mles/Stich) DON T FORGET: GFM = 1 MOLE = 6.02 x = 22.4L % ERROR FORMULA: (Math & Lab Skills)

18 % COMPOSITION FORMULA: (Mles/Stich) Ntes: Mass f whle is the gram frmula mass f the entire cmpund! CONCENTRATION FORMULAS: (Slutins) Ntes: Make sure yu are in grams fr ppm frmula! % by mass frmula is the same as the ppm except yu multiply by 100 instead f 1,000,000! Yu may need t cnvert frm grams t mles BEFORE using the mlarity equatin OR yu may need t cnvert t grams AFTER using the mlarity frmula, depending n the questin. COMBINED GAS LAW FORMULA: (Gases) Ntes: Be sure all units fr pressure, vlume, and temp are cnsistent, therwise yu must cnvert! Temperature must ALWAYS be in Kelvin (See temp cnversin frmula belw!) Knw relatinships between each variable in the equatin! At Cnstant Pressure: Eliminate the P variable frm the equatin (Charles s Law)! V1 = V2 T1 T2 At Cnstant Temp: Eliminate the T variable frm the equatin (Byle s Law)! P1V1 = P2V2 At Cnstant Vlume: Eliminate the V variable frm the equatin (Gay- Lussec s Law)! P1 = P2 T1 T2 TITRATION FORMULA: (Acids, Bases & Salts) Ntes: MA = Mlarity(Cncentratin) f Acid MB = Mlarity (Cncentratin) f Base T Find Vlume in Titratin Lab Applicatin Prblem: D: Final Vlume Initial Vlume befre plugging values int the equatin!

19 HEAT ENERGY FORMULAS: (Energy & Thermdynamics) Ntes: When the substance is water: Hf, Hv, and C values can be fund n Table B ΔT = Final Temp Initial Temp TEMPERATURE CONVERSION FORMULA: Matter & Energy & Thermdynamics)

20 The Peridic Table f Elements, first discvered in 1869 by Dmitry I. Mendeleyev gives a way f presenting and arranging all the elements in nature accrding t their similarities and differences. The elements are arranged in rder f increasing atmic number as yu g frm left t right acrss the table. The hrizntal rws = perids The vertical rws = grups Nble Gases = fund n the right hand side f each perid (Grup 18) As yu g frm left t right acrss each perid there is a prgressin frm metals (left) t metallids (alng the zigzag line) t nnmetals (right). Elements fund in each grup (i.e. alkali metals, halgens, etc ) have similar chemical prperties, and the same number f valence electrns in their utermst shell. As a result, elements in the same grup react similarly. The blck f elements in the middle f the peridic table (Grups 3-12) are called transitin metals. The elements with atmic numbers larger than 92 d nt ccur naturally. They have all been prduced artificially by bmbarding ther elements with particles. (Can be used as applicatin in varius packets) Use Carbn Key at the tp as a guide s yu knw where t find the atmic number, atmic mass, xidatin states, electrn cnfiguratin, etc fr each element Use each element bx t help yu figure ut the number f prtns, neutrns, electrns, atmic #, mass #, atmic mass, grund state electrn cnfiguratin, xidatin state, etc

21 Use the atmic mass as a check when calculating the average atmic mass fr all the naturally ccurring istpes f a particular element. The # f Principle Energy Levels fr an element = the amunt f # s in the electrn cnfiguratin. The last # in the electrn cnfiguratin = the # f valence electrns Example: Ca: ( ) = 4 PEL s ; 2 valence electrns Ne: 2-8 = 2 PEL s ; 8 valence electrns Use the grund state electrn cnfiguratin n the table t figure ut the excited state electrn cnfig. Use the xidatin state t help yu figure ut an elements tendency tward lsing/gaining electrns. Use the Peridic Table f Elements alng with Table S t help yu recgnize trends f the Peridic Table as yu g acrss a perid and dwn a grup. i.e. What happens t atmic #? What happens t the # f valence electrns? What happens t the atmic radius? What happens t the # f PEL s? etc Knw where metals, nnmetals and metallids are lcated n the peridic table! Lcatin n the peridic table als helps yu establish the type f bnd that exists between elements in a cmpund. Ex 1) Na (metal) + Cl (nnmetal) à inic bnd (transfer f electrns) Ex 2) H (nnmetal) + Cl (nnmetal) à cvalent bnd (sharing f electrns) Use the Peridic Table t help yu find the mlar mass/gram frmula mass f a mlecule.