thepage="Base Solutions(81)" //updated 11/18/02-netscape 7 //global variables refnumber=114 theanswer="" attempts=0 phans=0 corrt=0 totl=0 function parts(p1,p2,p3,p4,p5){ this.p1=p1 this.p2=p2 this.p3=p3 this.p4=p4 this.p5=p5 } function data(formula,name,K){ this.formula=formula this.name=name this.K=K } hsym="[OH-]" avalue="([Ci*Kb)1/2="+hsym bases=new Array() bases[0]=new data("C6H5NH2"," aniline ",4.3e-10) bases[1]=new data("C5H5N","pyridine",1.8e-9) bases[2]=new data("NH2OH","hydroxylamine",1.1e-8) bases[3]=new data("C10H14N2","nicotine",1e-6) bases[4]=new data("C17H19O3N","morphine",1.6e-6) bases[5]=new data("NH2NH2","hydrazine",1.7e-6) bases[6]=new data("NH3","ammonia",1.8e-5) bases[7]=new data("(CH3)3N","trimethylamine",6.5e-5) bases[8]=new data("CH3NH2","methylamine",3.6e-4) bases[9]=new data("(C2H5)3N","triethylamine",1e-3) function constants(){ var cont=window.open("","cont","scrollbars=yes,width=300,height=300") cont.document.writeln (""); cont.document.writeln ("Ionization Constants"); cont.document.writeln (""); cont.document.writeln ("Bases"); for(k=0;k<=9;k++){ if(k==25){cont.document.writeln ("")}; theK=bases[k].K theK=number(theK,2,2) cont.document.writeln("")}; cont.document.writeln("
Bases
",bases[k]['name'],""); cont.document.writeln("",showformula(k),""); cont.document.writeln("",theK,"
"); cont.document.writeln(""); cont.document.close(); cont.focus(); } checkstring="z0123456789" ansphrase=new Array() compare=new Array() compare[0]=new Array(" less "," valid") compare[1]=new Array(" greater "," invalid ") ansphrase[1]=new parts(" has a Kb of ",". First, calculate the value for the weak base approximation.
"," Since this is "," than 5% of the inital concentration ",", the approximate value is ",".") insphrase=new Array("
and the answer is pOH=","
and you must calculate the 'exact' answer using either successive approximations or the quadratic. This yields [OH-]=") pathway=new Array() pathway[0]=new Array(" less than "," valid ") pathway[1]=new Array(" greater than "," invalid ") function startit(){ clear() totl++ document.forms[0].results.value=document.forms[0].theans.value="" document.forms[0].total.value=totl which=Math.floor(bases.length*Math.random()) getconc() } function getconc(){ first=0 while(first<11)first=Math.ceil(100*Math.random()); conc="0."+zero()+first getanswer(which,conc) buildquest(which,conc) } function zero(){ added="" for(j=1;j<=Math.floor(3*Math.random());j++)added+="0"; return added } function getanswer(which,conc){ approx=Math.sqrt(conc*bases[which].K) check=.05*conc approx=number(approx,3,3) check=number(check,3,3) if(approx>check && Math.random()<.75){getconc()} else{ if(approx("+conc+"*"+number(bases[which].K,3,2)+")1/2="+number(approx,3,2) theanswer+=("
"+ansphrase[1].p3+compare[vkey][0]+ansphrase[1].p4+"("+number(check,3,2)+")"+ansphrase[1].p5+compare[vkey][1]+insphrase[vkey]) if(vkey==0)theanswer+=phans; else theanswer=theanswer+number(exans,3,3)+" and pH="+phans; } function buildquest(){ thequest="What is the pOH of a "+conc+"M solution of " Math.random()>.5?thequest+=(bases[which].name+"?"):thequest+=(getformula()+"?") showquest(thequest) } function answer(ans){ if(tried==1)alert("You've done this one. Get a new problem.") else{ if(tried==2){totl++;document.forms[0].total.value=totl} attempts++ if(ans>.95*phans & ans<1.05*phans){ document.forms[0].results.value="Correct" corrt++ document.forms[0].correct.value=corrt tried=1 } else{ document.forms[0].results.value="Incorrect" tried=2 }} } function showformula(k){ theformula="" teststring=bases[k].formula for(j=0;j0?theformula+=""+teststring.charAt(j)+"":theformula+=teststring.charAt(j); } return theformula } function getformula(){ theformula="" teststring=bases[which].formula for(j=0;j0?theformula+=""+teststring.charAt(j)+"":theformula+=teststring.charAt(j); } return theformula }