Time (s)Concentration of HCl (mol dm-3)Time (s)Concentration of CaCl2 (mol dm-3)Time (s)Volume of CO2 gas (cm3)Time (s)Mass ofCaCO3 (g)2t4541 CHEMISTRYChapter 1CHAPTER 1: RATE ! REACTI"1#$1: Rate o% reaction1. Rate of reaction is the chan&e in 'uantit( of reactant or pro)uct per unit time.Rate of reaction = Change in the quantit of reactant! "roductTime ta#en for the change2. $t is the spee) at %hich reactants are con&erted into the "roducts in a chemical reaction.3. Rate of reaction is in*ersel( "ro"ortional to time.Rate of reaction The shorter the time ta#en' the hi&her the rate of reaction. The lon&er the time ta#en' the lo+er the rate of reaction.(cti&it 1)-*tud the reaction +et%een 2., g of CaCO3 %ith e-cess of 1., mol dm-3 HCl.CaCO3(s) . 2HCl(aq)/ CaCl2(aq) . H2O(l) . CO2(g)*#etch the gra"h +elo% ),, ,,Chapter 1 Rate of Reaction10olume of gas(cm3)Time(s)0201t1 t2 t303The a*era&e rate of reaction in the first t1 second=The a*era&e rate of reaction ,et+een t1 secondand t2second= 0olume of gas (cm3)ta0201t1 t24541 CHEMISTRYChapter 11#$-: Measurin& the rate o% reaction1. T+o %as to measure the rate of reaction )(a) A*era&e rate o% reaction(&erage rate of reaction .Change in quantit of reactant! "roductTime ta#en for the change /etermination o% the a*era&e rate o% reaction %rom the &raph ) , (V1 1 ,) cm3

(t1 1 ,) s (V- 1 V1) cm3

(t- 1 t1) s (+) Instantaneous rate o% reaction ( Rate o% reaction at a &i*en time ) )=0ra)ient of the gra"h at a gi&en time#Chapter 1 Rate of ReactionThe a*era&e rate of reaction for the +hole reaction = The rate of reaction at ta second = 2radient of tangent to the cur&e at the gi&en time =(02 1 01) cm 3 (t2-t1) sTime (s)22ra"h of the &olumes of car+on dio-ide gas against time0olume ofcar+on dio-ide gas (cm3)1,2,3,3,3, 4,12, 15, 2,,4541 CHEMISTRYChapter 1(cti&it 2 )-(a) 6rite an equation for the a+o&e reaction. 777.77777777777777777777777777777(+) 8ra% a la+elled diagram to sho% the set-u" of the a""aratus in the e-"eriment.Chapter 1 Rate of Reaction(n e-"eriment is carried out to determine the rate of reaction +et%een calcium car+onate and dilute hdrochloric acid. The &olumes of car+on dio-ide gas e&ol&ed atfi-ed inter&als are recorded. 2ra"h of the &olumes of car+on dio-ide gas against time are sho%n +elo%.Time (s)34541 CHEMISTRYChapter 1(c) Calculate)(i)the a*era&e rate o% reaction for the %hole reaction.(ii)the instantaneous rate of reaction at 4# secon)s and 1# secon)s.at 3, seconds at 4, seconds(d) 9ase on the ans%er in (c) (ii)' %hich ha&e the hi&her rate of reaction. :-"lain our ans%er. 77777777.7777777777777777777777777777777777.77777777777777777777777777777777777777..7777777777777777777777777777777777777..7777777777777777777777777777777(e) *uggest another %a to increase the rate of a+o&e reaction7777777...777777.777777777777777777777777777777...777777.777777777777777777777777777777...777777.77777777777777777777777Chapter 1 Rate of Reaction34541 CHEMISTRYChapter 1(cti&it 3 )-2, cm3 of ,.; mol dm-3 hdrochloric acid is reacted %ith magnesium ri++on. The results are sho%n +elo%.Time 2s , 1; 3, 3; 5, rom the gra"h a+o&e ) The gradient of the cur&e %ith catalst is 777777. than the cur&e %ithout catalst. (t the end of this reaction' the total &olume of H2 gas in +oth reactions is the same +ecause the 777...... of Binc and sul"huric acid is the same.I Co""er ($$) sul"hate solution as catalst lo%ered the 777777...777 for the reaction. Therefore' more Binc atoms and hdrogen ions %ill +e a+le to o&ercome the lo%er777777777 The frequenc of e%%ecti*e collision +et%een the colliding "articles 77777.......... Therefore' rate of reaction ..777777777:-"eriment II )(a) $n this reaction' all other conditions such as &olume and concentration of hdrogen "ero-ide' tem"erature remain constant.2H2O2/2H2O.O2(f) 2ra"h sof &olume of o-gen gas "roduced against time are o+tained ),I >rom the gra"h ) The gradient of the cur&e using 1 spatula of KnO2 is 777777. than using : spatula ofKnO2. (t the end of this reaction' the total &olume of O2 gas in +oth reactions is the same +ecause the 7777777. of hdrogen "ero-ide is same.Chapter 1 Rate of Reaction13ptimum con)itions :Tem"erature ) 3;, oCJressure ) 2,, atmCatalst ) $ron' >e4541 CHEMISTRYChapter 1I Kanganese ($0) o-ide as catalst lo%ered the 777777777...7' Ea for the decom"osition of H2O2. Therefore' more hdrogen "ero-ide molecules %ill +e a+le to o&ercome the lo%er 777777777.. The frequenc of e%%ecti*e collision +et%een the colliding "articles 7777777.......... Therefore' the rate of reaction ..77777775$PressureI Onl for reactions in&ol&ing reactants in &aseous state.I 6hen the "ressure of the gaseous reactants increases' the "articles of the gaseous reactants are com"ressed to occu" a smaller *olume. Thus' the num+er of gas "articles "er unit &olume increases. The frequenc of collision +et%een "articles 777777.... The frequenc of e%%ecti*e collision 7777777 Therefore' the rate of reaction ..777.............1#$4: Application o% %actors that a%%ect the rate o% reaction 8ail li&es) Coo;in& o% soli) %oo) in smaller si6eThe total surface area e-"osed to heat on smaller cut "ieces of food is larger. Hence'the time ta#en for the food to +e coo#ed is shorter. Stora&e o% %oo) in a re%ri&erator 6hen the food #e"t in refrigerator' the food lasts longer. The lo% tem"erature in the refrigerator slo%s do%n the acti&it of the +acteria. Therefore' the rate of decom"osition of food is lo%er. Coo;in& in a pressure coo;er The high "ressure in "ressure coo#er increases the +oiling "oint of %ater to a tem"erature a+o&e 1,, C. Hence time ta#en for the food to +e coo#ed decreases. $n industr) Ha,er "rocessN manufacture of ammonia )D2 . 3H2/ 2DH3 Contact "rocessN manufacture of sul"huric acid @ catalst ) 0anadium(0) o-ide' 02O; A st+al) "rocessN manufacture of nitric acid @ catalst ) Jlatinum' Jt AChapter 1 Rate of Reaction13reactants

Ener&(Reaction "ath Eapro)uctsEaor a reaction to occur' the reactantHs "articles must collide.IDot all collisions result in chemical reactions.>>or a reaction to occur' the collisions must satisf t+o conditions)7i8 The colliding "articles must ha&e the ri&ht orientation of collision$7ii8 The colliding "articles must achie&e the minimum amount o% ener&( #no%n as the acti*ation ener&(? Ea$ > The collisions that lead to a chemical reaction are #no%n as e%%ecti*e collisions$1#$@: Ener&( Pro%ile /ia&ram and Acti*ation Ener&(? EaEa The acti&ation energ +ithout a catal(st$Ea