C3 - Chemical Economics
- Created by: helloiamjessica
- Created on: 02-04-15 03:43
C3A - Rate of Reaction (1)
DIFFERENT REACTION RATES
SLOW REACTIONS - RUSTING OF IRON, CHEMICAL WEATHERING
MODERATE SPEED REACTONS - METAL REACTING WITHDILUTE ACID - PRODUCE GENTLE STREAM BUBBLES
FAST REACTIONS - BURNING, EXPLOSIONS
EXPERIMENT TO FOLLOW A REACTION
MEASURING CHANGE IN MASS - CARRY OUT REACTION ON A BALANCE - MASS OF FLASK WILL FALL AS GAS IS RELEASED - TAKE READINGS OF MASS AT REGULAR TIME INTERVALS - USES FLASK, BUNSEN BURNER, TIMER
MEASURING VOLUME OF GAS GIVEN OFF - USE GAS SYRINGE TO MEASURE VOLUME OF GAS GIVEN OFF AFTER REGULAR TIME INTERVALS
STOPPING OF REACTIONS
YEILD OF REACTION DEPENDS ON AMOUNT OF REACTANT STARTED WITH - MORE REACTANT MEANS MORE PARTICALS - HAVE MORE REACTIONS - CREATE MORE PRODUCT
AMOUNT OF PRODUCT DIRECTLY PROPORTIONAL TO AMOUNT OF LIMITING REACTANT (REACTANT THAT'S TOTALLY USED UP DURING REACTION) - REACTION STOPS WHEN ALL LIMITING REACTANT IS USED UP
C3B - Rate of Reaction (2)
COLLISION THEORY
- RATE OF REACTION DEPENDS ON:
- COLLISION FREQUENCY OF PARTICLES - MORE COLLISIONS MEANS FASTER REACTIONS
- ENERGY TRANSFERED DURING COLLISION - PARTICLES HAVE TO COLLIDE WITH ENOUGH ENERGY FOR REACTION TO BE SUCCESSFUL
INCREASING TEMPERATURE
- PARTICLES MOVE MORE QUICKLY - COLLIDE MORE
- INCREASES ENERGY OF COLLISIONS - MORE PARTICLES COLLIDING WITH ENOUGH ENERGY TO REACT
INCREASING CONCENTRATION
MORE PARTICLES OF REACTANT IN SAME VOLUME - MAKES COLLISION MORE LIKELY - IN GAS, HIGHER PRESSURE MEANS PARTICLES ARE MORE CROWED - FREQUENCY OF COLLISIONS INCREASES
SMALLER SOLID PARTICLES
INCREASE SURFACE AREA OF REACTANT EXPOSED TO OTHER REACTANT - MORE SPACE TO WORK ON
C3C - Rate of Reaction (3)
CATALYSTS
- SUBSTANCE WHICH INCREASES SPEED OF REACTION WITHOUT BEING CHEMICALLY CHANGED OR USED UP IN REACTION
- ONLY NEED A TINY BIT OF CATALYST TO CATALYSE LARGE AMOUNTS OF REACTANTS - ISN'T USED UP
- SPECIFIC CATALYSTS CATALYSE SPECIFIC REACTIONS - CATALYSTS AREN'T UNIVERSAL
- WORKS BY GIVING REACTING PARTICLES A SURFACE TO STICK TO WHERE THEY CAN BUMP INTO EACHOTHER - REDUCES ENERGY NEEDED BY PARTICLES TO REACT - OVERALL NUMBER OF COLLISIONS NOT INCREASED BUT NUMBER OF SUCCESSFUL COLLISIONS IS
LUMP AND POWDERED REACTANTS
- POWDERED REACTANT REACTS QUICKER - SMALLER PARTICLES - MORE SURFACE AREA EXPOSED TO SUBSTANCE IT'S REACTING WITH THAN A LUMP REACTANT OF SAME MASS - MORE AREA FOR REACTING SUBSTANCES TO WORK ON
C3C - Rate of Reaction Data
INTERPRETING DATA ON REACTION RATES
- DETERMINE HOW MUCH PRODUCT IS PRODUCES WHEN REACTION FINISHES (LIMITING REACTANT USED UP) - WHERE ON AXIS LABELED 'VOLUME' LINE GOES FLAT
- DETERMINE HOW LONG REACTION TOOK - WHERE ON AXIS LABELED 'TIME' LINE GOES FLAT
- EXTRAPOLATION - DETERMINING VALUE THAT IS NOT VISIBLE ON GRAPH BY ASSUMING THAT GRAPH FOLLOWS LOGICALLY THE SAME PATTERN AS THE DATA THAT IS VISIBLE
- INTERPOLATION - CONSTRUCTING NEW DATA POINTS ACCORDING TO ESTIMATE BASED ON PATERN THAT VISIBLE DATA FOLLOWS
- COMPARING TWO REACTIONS - WHICH REACTION IS FASTER - WHICH LINE GOES FLAT FIRST, WHICH LINE IS STEEPER
- WHEN CONCLUDING, TALK ABOUT DIRECT POINTS ON GRAPH AND LINK IT TO OWN KNOWLEDGE ON COLLISION THEORY
C3D - Reacting Masses
REACTING MASSES
- RELATIVE ATOMIC MASS - BIGGER NUMBER OF TWO NUMBERS FOR EACH ELEMENT - MASS OF PROTONS AND NEUTRONS IN NUCLEUS OF ELEMENT
- RELATIVE FORMULA MASS - ALL RELATIVE ATOMIC MASSES OF INDIVIDUAL ELEMENTS IN COMPOUND ADDED TOGETHER
MASS CONSERVED
- DURING CHEMICAL REACTION, NO ATOMS ARE DESTROYED AND NO ATOMS ARE CREATED - SAME NUMBER AND TYPES OF ATOM ON EACH SIDE OF EQUASION
- YOU CAN SEE THAT MASS IS CONSERVED BY ADDING UP RELATIVE FORMULA MASSES ON EACH SIDE OF EQUASION
- NEED TO BE ABLE TO BALANCE EQUASIONS
C3D - Reacting Masses
CALCULATING MASSES IN REACTIONS - THREE STEPS
- - WORK OUT BALANCED EQUASION
- - WORK OUT RELATIVE FORMULA MASS FOR TWO BITS YOU WANT
- - DIVIDE TO GET ONE, THEM MULTIPLY OUT TO GET ALL
- E.G. CALCULATE MASS OF MAGNESIUM OXIDE PRODUCED WHEN 60g MAGNESIUM BURNED IN AIR
- - BALANCED EQUASION: 2Mg +O2 ---> 2MgO
- - RELATIVE FORMULA MASS OF MAGNESIUM - 48
- - RELATIVE FORMULA MASS OF MAGNESIUM OXIDE PRODUCED - 80
- 48g MAGNESIUM REACTS TO GIVE 80g OF MAGNESIUM OXIDE - DIVIDE BOTH SIDES BY 48 TO GET AMOUNT PRODUCED FOR 1g OF MAGNESIUM AND THEN MULTIPLY BY AMOUNT OF G BURNED (60) - (80 / 48) X 60 = 100g 60g MAGNESIUM REACTS TO GIVE 100G OF MAGNESIUM OXIDE
C3E - Percentage Yield and Atom Economy
PERCENTAGE YIELD
- PERCENTAGE YIELD = (ACTUAL YEILD (G) / PREDICTED YEILD (G)) X 100
- PREDICTED YIELD OF A REACTION - CALCULATED BY LOOKING AT FORMULA MASSES OF BALANCED EQUASIONS
- PERCENTAGE YEILD ALWAYS BETWEEN 0 AND 100 PERCENT - 100% MEANS ALL REACTANT WAS CONVERTED INTO PRODUCT, 0% MEANS NO REACTANT CONVERTED INTO PRODUCT
- PERCENTAGE YEILD CAN NEVER BE 100% BECAUSE SOME REACTANT IS ALWAYS LOST THROUGH:
- EVAPORATION - LIQUIDS CONSTANTLY EVAPORATING - EVEN MORE SO WHEN BEING HEATED
- NOT ALL REACTANTS REACT TO MAKE PRODUCT - IN REVERSABLE REACTIONS, PRODUCTS CAN TURN BACK INTO REACTANTS - YIELD WILL NEVER BE 100%
- FILTRATION - WHEN LIQUID IS FILTERED TO REMOVE SOLID PARTICLES, A BIT OF THE LIQUID OR SOLID IS ALWAYS LOST - IF LIQUID NEEDS TO BE KEPT, A BIT THAT REMAINS WITH SOLID AND FILTER PAPER IS LOST - IF YOU WANT TO KEEP SOLID, BITS THAT GET LEFT BEHIND WHEN SCRAPED OFF FILTER PAPER IS LOST
- TRANSFERING LIQUIDS - ALWAYS LOSE A BIT OF LIQUID WHEN IT'S TRANSFERED FROM ONE CONTAINER TO ANOTHER - SOME BITS ALWAYS GET LEFT BEHIND ON SURFACE OF CONTAINER LIQUID IS BEING TRANSFERED FROM - ALWAYS WET WHEN FINISHED
C3E - Percentage Yield and Atom Economy
ATOM ECONOMY
- ATOM ECONOMY = (TOTAL FORMULA MASS OF DESIRED PRODUCTS / TOTAL FORMULA MASS OF ALL PRODUCTS) X 100
- 100% ATOM ECONOMY MEANS THAT ALL REACTANTS HAVE BEEN TURNED INTO USEFUL PRODUCTS
- E.G. ATOM ECONOMY OF REACTION OF METHANE AND STEAM TO GET HYDROGEN GAS
- CH4 + H2O ---> CO + 3H2
- - IDENTIFY USEFUL PRODUCT - HYDROGEN
- - WORK OUT FORMULA MASS OF ALL PRODUCTS AND THEN FORMULA MASS OF ALL USEFUL PRODUCTS
- ALL PRODUCTS = 34
- HYDROGEN = 6
- PUT IT INTO EQUASION - (34 / 6) X 100 = 17.6%
C3E - Percentage Yield and Atom Economy
ECONOMIC ADVANTAGES OF HIGH ATOM ECONOMY
- REACTIONS WITH LOW ATOM ECONOMY USE UP RECOURCES VERY QUICKLY AND MAKE A LOT OF WASTE
- RAW MATERIALS NEEDED FOR REACTIONS ARE EXPENSIVE
- DISPOSAL OF WASTE PRODUCTS CAN BE EXPENSIVE - NEED TO FIND A WAY TO REUSE WASTE PRODUCTS RATHER THAN JUST DISPOSING OFTHEM
- LOW ATOM ECONOMY REACTIONS NOT PROFITABLE - HIGH ATOM ECONOMY MEANS THEY ONLY HAVE ONE PRODUCT SO MOST MONEY SPENT ON RAW MATERIALS (REACTANTS) IS NOT WASTED
ENVIRONMENTAL ADVANTAGES OF HIGH ATOM ECONOMY
- DISPOSAL OF WASTE PRODUCTS - BAD FOR ENVIRONMENT - LANDFILL SITES WASTE SPACE - BURNING RELEASES TOXIC GASES
- MORE RAW MATERIALS NEEDED MEANS MORE UNRENEWABLE RECOURCES BEING USED UP FOR NOT A LOT OF RESULT
C3F - Energy
- EXOTHERMIC REACTIONS - REACTIONS THAT GIVE OUT ENERGY TO SURROUNDINGS USUALLY IN FORM OF HEAT - SHOWN BY RISE IN TEMPERATURE
- ENDOTHERMIC REACTIONS - REACTIONS THAT TAKE IN ENERGY FROM SURROUNDINGS USUALLY IN FORM OF HEAT - SHOWN BY FALL IN TEMPERATURE
- EXPERIMENT - MEASURE TEMPERATURE OF INDIVIDUAL REACTANTS AND THEN MIX THEM AND MEASURE TEMPERATURE OF MIXTURE
- ADDING ACID TO ALKALI - EXOTHERMIC REACTION - TEMPERATURE INCREASES WHEN ACID AND ALKALI MIX
- DISSOLVING AMMONIUM NITRATE IN WATER - ENDOTHERMIC REACTION - TEMPERATURE DECREASES WHEN AMMONIUM NITRATE IS DISSOLVED
BONDS - CHEMICAL REACTION - OLD BONDS BROKEN AND NEW BONDS FORMED
- ENERGY SUPPLIED TO BREAK BONDS - BONDS BREAKING IS ENDOTHERMIC - ENERGY RELEASED WHEN BONDS FORM - BONDS FORMING IS EXOTHERMIC
- EXOTHERMIC REACTIONS - ENERGY RELEASED IN BONDS FORMING GREATER THAN ENERGY TAKEN IN WHEN BONDS BREAK
- ENDOTHERMIC REACTION - ENERGY TAKEN IN WHEN BONDS BREAK IS GREATER THAN ENERGY GIVEN OUT WHEN BONDS FORM
C3F - Energy
SPECIFIC HEAT CAPACITY
- CALOMETRIC EXPERIMENT - INVOLVES HEATING WATER BY BURNING LIQUID FUEL
- IF YOU MEASURE HOW MUCH FUEL YOU'VE BURNED AND THE TEMPERATURE CHANGE OF THE WATER, YOU CAN WORK OUT HOW MUCH ENERGY IS SUPPLIED FOR EACH GRAM OF FUEL
- ALSO NEED TO KNOW SPECIFIC HEAT CAPACITY OF WATER - 4.2 J TO RAISE TEMP BY 1 DEGREE
- DO SAME EXPERIMENT WITH DIFFERENT FUELS, COMPARE ENERGY TRANSFERRED WITH EACH FUEL - FUEL WITH HIGHER ENERGY CONTENT PER GRAM MEANS YOU NEED LESS TO RAISE TEMP BY SAME AMOUNT
METHOD
- IMPORTANT TO REDUCE HEAT LOSS AS MUCH AS POSSIBLE - USE SCREEN TO ACT AS DRAUGH EXCLUDER
- PUT FUEL INTO SPIRIT BURNER AND WEIGH BURNER FULL OF FUEL
- MESURE OUT 200CM WATER INTO COPPER CALORIMETER
- TAKE INITIAL TEMP OF WATER AND PUT BURNER UNDER CALORIMETER AND LIGHT
- WHEN TEMP OF WATER HAS RISEN BY 20-30 DEGREES, PUT OUT SPIRIT BURNER AND MAKE NOTE OF HIGHEST TEMP THE WATER REACHES
- REWEIGH BURNER OF FUEL
C3F - Energy
CALCULATIONS
- FIND OUT MASS OF FUEL BURNED BY SUBTRACTING FINAL MASS OF FUEL BURNER FROM INITIAL MASS
- ENERGY TRANSFERED (J) = MASS OF WATER (G) X SPECIFIC HEAT CAPACITY OF WATER X TEMP CHANGE (C)
- ENERGY GIVEN OUT PER GRAM = ENERGY RELEASED (J) / MASS OF FUEL BURNED (G)
FAIR TEST
- TO COMPARE ENERGY CONTENT OF DIFFERENT FUELS THE SAME EXPERIEMNT NEEDS TO BE DONE SEVERAL TIMES, USING DIFFERENT FUELS EACH TIME
- FOR COMPARISON TO BE FAIR, EVERYTHING EXCEPT FUEL USED NEEDS TO BE THE SAME
- SAME APPERATUS SHOULD BE USED
- SAME AMOUNT OF WATER SHOULD BE USED
- WATER SHOULD START AND FINISH AT SAME TEMPERATURE EACH TIME
- FOR RELIABLE RESULTS, REPEAT EXPERIMENT WITH SAME FUEL SEVERAL TIMES AND DICOUNT ANOMOLOUS RESULTS
C3G - Batch or Continuous?
BATCH PRODUCTION
- ONLY OPERATES AT CERTAIN TIMES - USED FOR COMPLICATED DRUGS WITH FAIRLY LOW DEMAND
- ADVANTAGES - FLEXIBLE - SEVERAL DIFFERENT PRODUCTS CAN BE MADE USING SAME EQUIPMENT
- START UP COSTS RELATIVELY LOW - SMALL SCALE, MULTI PURPOSE EQUIPMENT CAN BE BOUGHT OFF THE SHELF
- DISADVANTAGES - LABOUR INTENSIVE - EQUIPMENT NEEDS TO BE SET UP MANUALLY, CONTROLLED FOR EACH BATCH AND CLEARED OUT AT END
- CAN BE TRICKY TO KEEP SAME QUALITY FROM BATCH TO BATCH
CONTINUOUS PRODUCTION
- RUNS ALL THE TIME - USED FOR LARGE SCALE INDUSTRIAL MANUFACTURE OF POPULAR CHEMICALS
- ADVANTAGES - PRODUCTION NEVER STOPS - NO TIME WASTED CLEARING UP AND SETTING UP AGAIN
- RUNS AUTOMATICALLY - NO LABOUR UNLESS SOMETHING GOES WRONG
- QUALITY OF PRODUCT VERY CONSISTANT
- DISADVANTAGES - START UP COSTS HUGE, NOT COST EFFECTIVE IF RUN LESS THAN FULL CAPACITY
C3G - Batch or Continuous?
PHARMACEUTICAL DRUGS
- COMPLICATED AND FAIRLY EXPENSIVE TO MAKE - FAIRLY LOW DEMAND - BATCH PRODUCTION MOST COST EFFECTIVE WAY - PRODUCTION HAS SEVERAL STAGES:
- RESEARCH AND DEVELOPMENT - FINDING A SUITABLE COMPOUND, TESTING, MODIFYING, RETESTING - INVOLVES WORK OF A LOT OF HIGHLY PAID SCIENTISTS
- TRIALLING - NO DRUG ALLOWED TO BE MANUFACTURED UNLESS IT'S BEEN TRIALED - TIME CONSUMING - ANIMAL AND HUMAN TRIALS - PROVE THAT DRUG MEETS LEGAL REQUIREMENTS AND IS SAFE
- MANUFACTURE - MULTI STEP BATCH PRODUCTION - LABOUR INTENSIVE - CAN'T BE AUTOMATED
- RAW MATERIALS AND ENERGY FOR MANUFACTURE COST MONEY - RAW MATERIALS OFTEN RARE - EXTRACTED USING CERTAIN METHOD:
- TO EXTRACT SUBSTANCE FROM PLANT, IT HAS TO BE CRUSHED, BOILED AND DISSOLVED IN SOLUBLE SOLVENT - SUBSTANCES THEN EXTRACTED BY CHROMATOGRAPHY
TESTING FOR PURITY
- IMPURE SUBSTANCES WON'T BE SEPERATED BY CHROMATOGRAPHY
- IMPURE SUBSTANCE - NO SPECIFIC MELT TEMPS, MELTING POINT TOO LOW AND BOILING POINT TOO HIGH
C3H - Allotropes of Carbon and Nanochemistry
PROPERTIES OF DIAMOND
- LUSTROUS AND COLOURLESS - IDEAL FOR JEWELLERY
- HARD - EACH CARBON ATOM FORMS FOUR COVALENT BONDS IN VERY RIGID, GIANT COVELENT STRUCTURE - USED FOR CUTTING TOOLS
- VERY HIGH MELTING POINT - COVALENT BONDS TAKE A LOT OF ENERGY TO BREAK - GOOD CUTTING TOOL
- DOESN'T CONDUCT ELECTRICITY - NO FREE ELECTRONS
C3H - Allotropes of Carbon and Nanochemistry
PROPERTIES OF GRAPHITE
- BLACK AND OPAQUE BUT STILL SHINY
- EACT CARBON FORMS THREE COVALENT BONDS, CREATING SHEETS OF CARBON ATOMS FREE TO SLIDE OVER EACHOTHER
- LAYERS CAN BE RUBBED OFF ONTO PAPER - LEAVES BLACK MARK - LAYERS HELD TOGETHER WEAKLY - SLIPPERY - USED IN PENCILS
- CONDUCTS ELECTRICITY - THREE COVELENT BONDS - LOTS OF DELOCALISED ELECTRONS
- HIGH MELTING POINT - COVALENT BONDS - A LOT OF ENERGY TO BREAK
C3H - Allotropes of Carbon and Nanochemistry
GIANT MOLECULAR STRUCTURES
- CARBON CAN FORM LOTS OF COVALENT BONDS WITH ITSELF - CAN FORM LOTS OF GIANT MOLECULAR STRUCTURES - DIAMOND AND GRAPHITE SHEETS
- STRONG, HIGH MELTING POINTS, DON'T DISSOLVE IN WATER - COVALENT BONDS
- DON'T CONDUCT ELECTRICITY - NO DELOCALISED ELECTRONS - GRAPHITE IS AN ACCEPTION
FULLERINES
MOLECULES OF CARBON SHAPED LIKE CLOSED TUBES OR HOLLOW BALLS - NANOPARTICLES
- CAN BE USED TO CAGE OTHER MOLECULES - FORMS AROUND ANOTHER ATOM OR MOLECULE WHICH IS THEN TRAPPED INSIDE - NEW WAY OF DELIVERING DRUG INTO BODY FOR SLOW RELEASE
- CAN BE JOINED TOGETHER TO FORM NANOTUBES - TINY HOLLOW CARBON TUBES
NANOTUBES - HUGE SURFACE AREA - MAKE GOOD INDUSTRIAL CATALYSTS - INDIVIDUAL CATALYST MOLECULES COULD BE ATTATCHED TO NANOTUBE
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