thepage="Freezing/Boiling Points of Aqueous Solutions"
//11/20/02-updated netscape 7
//global variables
alldata=0
attempts=0
which=0
theanswer=0
corrt=0
totl=0
option=0
thesolution=""
tests=0
//This function creates array elements with four properties, formula,gfw and
//"particles" per formula unit,and the gs(g/100mL). If the material is highly
//miscible with water, its gs is set at 25g.
function solute(formula,gfw,parts,gs){
	this.formula=formula
	this.gfw=gfw
	this.parts=parts
	this.gs=gs
}
//This creates an array of solutes with 20 elements
cmpd=new Array();
//The following are the elements in the item array which have the properties
//shown in solute
cmpd[0]=new solute("CsCl",168.4,2,25);
cmpd[1]=new solute("NaCl",58.45,2,25)
cmpd[2]=new solute("NaNO3",85,2,25)
cmpd[3]=new solute("KI",166,2,25)
cmpd[4]=new solute("KOH",56,2,25)
cmpd[5]=new solute("Ca(NO3)2",164,3,25)
cmpd[6]=new solute("CH3OH",32,1,25)
cmpd[7]=new solute("HCl",36.5,2,25)
cmpd[8]=new solute("ethanol",46,1,25)
cmpd[9]=new solute("LiBr",104.9,2,25)
cmpd[10]=new solute("Fe(NO3)3",242,4,25)
cmpd[11]=new solute("Mg(NO3)2",148,3,25)
cmpd[12]=new solute("HNO3",63,2,25)
cmpd[13]=new solute("CaI2",294,3,25)
cmpd[14]=new solute("Co(NO3)2",183,3,25)
cmpd[15]=new solute("Na2SO4",142.08,3,27.8)
cmpd[16]=new solute("NaOH",40.01,2,25)
cmpd[17]=new solute("KNO2",85.1,2,25)
cmpd[18]=new solute("HI",128,2,25)
//They are then passed to the calculate function
symbols=new Array("dT<sub>b</sub>","dT<sub>f</sub>","K<sub>b</sub>","K<sub>f</sub>","<i>m</i>","T<sub>b</sub>","T<sub>f</sub>","grams(H<sub>2</sub>O)","kg(H<sub>2</sub>O)","mass(solute)","gfw(solute)","DF","moles(solute)")
ansphrase=new Array("First, calculate the 'effective' moles of solute by calculating actual moles and then multiplying by the number of 'particles' per mole (here we use the symbol 'DF'-dissolving factor for that term).<br>","<br>Then, after determing the number of kg of solvent, calculate the molality.<br>","<br>The boiling point elevation and freezing point depression are determined by multiplying the molality by the appropriate constants.<br>","<br>Finally, the resultant boiling and freezing points for the solution are calculated using the 'normal' values.<br>")  
solved=0
equations=new Array()
equations[0]=symbols[0]+"="+symbols[2]+"*"+symbols[4]//dTb=Kb*m
equations[1]=symbols[1]+"="+symbols[3]+"*"+symbols[4]//dTb=Kb*m
equations[2]=symbols[5]+"=100+"+symbols[0]//Tb=100+dTb
equations[3]=symbols[6]+"=0.00-"+symbols[1]//Tf=0-dTf
equations[4]=symbols[8]+"="+symbols[7]+"/1000"//kg=g/1000
equations[5]=symbols[12]+"="+symbols[11]+"*"+symbols[9]+"/"+symbols[10]//effmolessolute=DF*mass/gfw
equations[6]=symbols[4]+"="+symbols[12]+"/"+symbols[8]//m=mass/kg
alldata=new Array()
alldata[2]=.512
alldata[3]=1.86
function clear(){
	attempts=0
	tried=0
	for(j=0;j<5;j++)document.forms[0].elements[j].value=""
	clearansspot()
	document.forms[0].results.value=""
}
function startit(){
	clear()
	totl++
	document.forms[0].total.value=totl
	which=Math.floor(cmpd.length*Math.random())
	alldata[10]=cmpd[which].gfw
	alldata[9]=0
	while(alldata[9]<2 || alldata[9]>cmpd[which]["gs"])alldata[9]=25*Math.random();
	alldata[7]=0
	while(alldata[7]<200)alldata[7]=700*Math.random();
      calculate()
}
function calculate(){
	alldata[11]=cmpd[which].parts
	alldata[12]=alldata[11]*alldata[9]/alldata[10]
	alldata[8]=alldata[7]/1000
	alldata[4]=alldata[12]/alldata[8]
	alldata[0]=alldata[2]*alldata[4]
	alldata[1]=alldata[3]*alldata[4]
	alldata[5]=100+alldata[0]
	alldata[6]=alldata[1]
	for( var j=0;j<alldata.length;j++){
		if(j!=5)alldata[j]=number(alldata[j],4,3);
	}
	alldata[11]=Math.round(alldata[11])
	alldata[5]=number(alldata[5],5,3)
	compd=cmpd[which].formula
	if(alldata[1]<.5){totl--;startit()}
	else  buildquest()
}
//This function creates the problem and the answer method by filling the first three cells
function buildquest(){
	document.forms[0].cpd.value=compd
	document.forms[0].solute.value=alldata[9]
	document.forms[0].solvent.value=alldata[7]
	buildanswer()	
}
function buildanswer(){
	getsolved()
	theanswer=ansphrase[0]+equations[5]+"=>"+solved[5]+ansphrase[1]+equations[4]+"=>"+solved[4]+"<br>"+equations[6]+"=>"+solved[6]+ansphrase[2]+equations[0]+"=>"+solved[0]+"<br>"+equations[1]+"=>"+solved[1]+ansphrase[3]+equations[2]+"=>"+solved[2]+"<br>"+equations[3]+"=>"+solved[3]
}
function getsolved(){
	solved=new Array()
	solved[0]=alldata[2]+"*"+alldata[4]+"="+alldata[0]//dTb=Kb*m
	solved[1]=alldata[3]+"*"+alldata[4]+"="+alldata[1]//dTb=Kb*m
	solved[2]=100+"+"+alldata[0]+"="+alldata[5]//Tb=100+dTb
	solved[3]="0.00-"+alldata[1]+"=-"+alldata[6]//Tf=0-dTf
	solved[4]=alldata[7]+"/1000="+alldata[8]//kg=g/1000
	solved[5]=alldata[11]+"*"+alldata[9]+"/"+alldata[10]+"="+alldata[12]//effmolessolute=DF*mass/gfw
	solved[6]=alldata[12]+"/"+alldata[8]+"="+alldata[4]//m=mass/kg
}
// This is the "Check Answer Function
function answer(){
	if(tried==1)alert("You've already done this one. Get a new problem!");
	else{
	attempts++
	test=0
	if(tried==2){totl++; document.forms[0].total.value=totl}
	if(document.forms[0].fp.value<-.95*alldata[6] & document.forms[0].fp.value>-1.05*alldata[6])test++;
	if(document.forms[0].bp.value>.95*alldata[5] & document.forms[0].bp.value<1.05*alldata[5])test++;
	if(test==2){
		document.forms[0].results.value="correct";
		corrt++
		document.forms[0].correct.value=corrt
		tried=1
	}
	else {
		document.forms[0].results.value="incorrect"
		tried=2
		}
	}
}