//Acids & Bases - Acid/Base Equilibrium Constant Script
thepage="Acid/Base Equilibrium Constant"
//updated 11/18/02-netscape 7
//global variables
//refnumber=121
theanswer=""
attempts=0
tried=0
anrs=0
corrt=0
totl=0
ctype=0
first=0
second=0
option=0
acidk=0
basek=0
theanswer=""
K=0
cmpd=new Array()
thereaction=""
ansset=new Array()
neat=new Array()
showK=new Array()
//the following area is the data:name of species, formula,formula of conjugate
//K value and type
compound=new Array()
compound[0]=new Array("CH<SUB>3</SUB>COOH","CH<SUB>3</SUB>COO<SUP>-</SUP>",1.8e-5)
compound[1]=new Array("C<SUB>3</SUB>H<SUB>4</SUB>O<SUB>2</SUB>","C<SUB>3</SUB>H<SUB>3</SUB>O<SUB>2</SUB><SUP>-</SUP>",5.5e-5)
compound[2]=new Array("C<SUB>7</SUB>H<SUB>6</SUB>O<SUB>2</SUB>","C<SUB>7</SUB>H<SUB>5</SUB>O<SUB>2</SUB><SUP>-</SUP>",6.3e-5)
compound[3]=new Array("C<SUB>2</SUB>H<SUB>3</SUB>ClO<SUB>2</SUB>","C<SUB>2</SUB>H<SUB>2</SUB>ClO<SUB>2</SUB><SUP>-</SUP>",1.4e-3)
compound[4]=new Array("HClO<SUB>2</SUB>","ClO<SUB>2</SUB><SUP>-</SUP>",1.1e-2)
compound[5]=new Array("HOCN","OCN<SUP>-</SUP>",3.5e-4)
compound[6]=new Array("HCO<SUB>2</SUB>H","HCO<SUB>2</SUB><SUP>-</SUP>",1.8e-4)
compound[7]=new Array("HF","F<SUP>-</SUP>",6.6e-4)
compound[8]=new Array("HNO<SUB>2</SUB>","NO<SUB>2</SUB><SUP>-</SUP>",7.2e-4)
compound[9]=new Array("HN<SUB>3</SUB>","N<SUB>3</SUB><SUP>-</SUP>",1.9e-5)
compound[10]=new Array("C<SUB>3</SUB>H<SUB>6</SUB>O<SUB>2</SUB>","C<SUB>3</SUB>H<SUB>5</SUB>O<SUB>2</SUB><SUP>-</SUP>",1.3e-5)
compound[11]=new Array("HOCl","OCl<SUP>-</SUP>",2.9e-8)
compound[12]=new Array("C<SUB>2</SUB>H<SUB>2</SUB>Cl<SUB>2</SUB>O<SUB>2</SUB>","C<SUB>2</SUB>H<SUB></SUB>Cl<SUB>2</SUB>O<SUB>2</SUB><SUP>-</SUP>",5.5e-2)
compound[13]=new Array("C<SUB>6</SUB>H<SUB>5</SUB>SH","C<SUB>6</SUB>H<SUB>5</SUB>S<SUP>-</SUP>",3.2e-7)
compound[14]=new Array("C<SUB>4</SUB>H<SUB>8</SUB>O<SUB>2</SUB>","C<SUB>4</SUB>H<SUB>7</SUB>O<SUB>2</SUB><SUP>-</SUP>",1.5e-5)
compound[15]=new Array("C<SUB>8</SUB>H<SUB>8</SUB>O<SUB>2</SUB>","C<SUB>8</SUB>H<SUB>7</SUB>O<SUB>2</SUB><SUP>-</SUP>",4.9e-5)
compound[16]=new Array("C<SUB>2</SUB>H<SUB>3</SUB>FO<SUB>2</SUB>","C<SUB>2</SUB>H<SUB>2</SUB>FO<SUB>2</SUB><SUP>-</SUP>",2.6e-3)
compound[17]=new Array("C<SUB>2</SUB>HCl<SUB>3</SUB>O<SUB>2</SUB>","C<SUB>2</SUB>Cl<SUB>3</SUB>O<SUB>2</SUB><SUP>-</SUP>",.3)
compound[18]=new Array("C<SUB>5</SUB>H<SUB>5</SUB>NCl","C<SUB>5</SUB>H<SUB>4</SUB>NCl<SUP>-</SUP>",6.67e-6)
//weak bases start here
compound[19]=new Array("NH<SUB>3</SUB>","NH<SUB>4</SUB><sup>+</sup>",1.8e-5)
compound[20]=new Array("C<SUB>6</SUB>H<SUB>5</SUB>NH<SUB>2</SUB>","C<SUB>6</SUB>H<SUB>5</SUB>NH<SUB>3</SUB><sup>+</sup>",7.4e-10)
compound[21]=new Array("C<SUB>18</SUB>H<SUB>21</SUB>NO<SUB>3</SUB>","C<SUB>18</SUB>H<SUB>22</SUB>NO<SUB>3</SUB><sup>+</sup>",8.9e-7)
compound[22]=new Array("C<SUB>2</SUB>H<SUB>5</SUB>NH<SUB>2</SUB>","C<SUB>2</SUB>H<SUB>5</SUB>NH<SUB>3</SUB><sup>+</sup>",4.3e-4)
compound[23]=new Array("C<SUB>5</SUB>H<SUB>11</SUB>N","C<SUB>5</SUB>H<SUB>12</SUB>N<sup>+</sup>",1.3e-3)
compound[24]=new Array("(C<SUB>2</SUB>H<SUB>5</SUB>)<SUB>3</SUB>N","(C<SUB>2</SUB>H<SUB>5</SUB>)<SUB>3</SUB>NH<sup>+</sup>",5.2e-4)
compound[25]=new Array("(CH<SUB>3</SUB>)<SUB>3</SUB>N","(CH<SUB>3</SUB>)<SUB>3</SUB>NH<sup>+</sup>",6.3e-5)
compound[26]=new Array("NH<SUB>2</SUB>OH","NH<SUB>3</SUB>OH<sup>+</sup>",9.1e-9)
compound[27]=new Array("CN<sup>-</sup>","HCN", 1.61e-5 )
compound[28]=new Array("OBr<sup>-</sup>","HOBr",4e-6)
compound[29]=new Array("CH<SUB>3</SUB>NH<SUB>2</SUB>","CH<SUB>3</SUB>NH<SUB>3</SUB><sup>+</sup>",4.2e-4)
compound[30]=new Array("C<SUB>17</SUB>H<SUB>19</SUB>NO<SUB>3</SUB>","C<SUB>17</SUB>H<SUB>20</SUB>NO<SUB>3</SUB><sup>+</sup>",7.4e-7)
compound[31]=new Array("(C<SUB>2</SUB>H<SUB>5</SUB>)<SUB>2</SUB>NH","(C<SUB>2</SUB>H<SUB>5</SUB>)<SUB>2</SUB>NH<sub>2</sub><sup>+</sup>",6.9e-4)
compound[32]=new Array("(CH<SUB>3</SUB>)<SUB>2</SUB>NH  ","(CH<SUB>3</SUB>)<SUB>2</SUB>NH<sub>2</sub><sup>+</sup>",5.9e-4)
compound[33]=new Array("OI<sup>-</sup>","HOI",4.35e-4)
compound[34]=new Array("C<SUB>6</SUB>H<SUB>15</SUB>NO<SUB>3</SUB>","C<SUB>6</SUB>H<SUB>16</SUB>NO<SUB>3</SUB><sup>+</sup>",5.8e-7)
compound[35]=new Array("C<SUB>5</SUB>H<SUB>5</SUB>N","C<SUB>5</SUB>H<SUB>6</SUB>N<sup>+</sup>",1.5e-9)
compound[36]=new Array("N<SUB>2</SUB>H<SUB>4</SUB>","N<SUB>2</SUB>H<SUB>5</SUB><sup>+</sup>",8.5e-7)
function constants(){
var cont=window.open("","cont","scrollbars=yes,width=300,height=300")
cont.document.writeln ("<html>");
cont.document.writeln ("<head><title>Ionization Constants</title>");
cont.document.writeln ("</head>");
cont.document.writeln ("<body bgcolor = FFFFFF><b>Acids</b><table>");
for(k=0;k<=36;k++){
if(k==19){cont.document.writeln ("<tr><td><b>Bases</b><br></td></tr>")};
cont.document.writeln("<tr><td>",compound[k][0],"</td><td>");
cont.document.writeln("<td>",number(compound[k][2],2,2),"</td></tr>")};
cont.document.writeln("</table><form><input type=button value='Close Window' onClick='window.close()'></form>");
cont.document.writeln("<html>");
cont.document.close();
cont.focus();
}
function startit(){
	clear()
	totl++
	document.forms[0].total.value=totl
	getspecies()
}
function getspecies(){
	first=Math.floor(19*Math.random())
	if(Math.random()>.5){
		option=1
		cmpd[0]=compound[first][0]
		cmpd[2]=compound[first][1]
		k1=compound[first][2]
		acidk=0
	}
	else{
		option=2
		cmpd[1]=compound[first][1]
		cmpd[3]=compound[first][0]
		k2=1e-14/compound[first][2]
		basek=1
	}
	second=first
	while(second==first){second=Math.floor(37*Math.random())
	if(option==1){
		if(second<19){
			cmpd[1]=compound[second][1]
			cmpd[3]=compound[second][0]
			k2=1e-14/compound[second][2]
			basek=2
		}
		else{
			cmpd[1]=compound[second][0]
			cmpd[3]=compound[second][1]
			k2=compound[second][2]
			basek=0
		}
	}
	else
		if(second<19){
			cmpd[0]=compound[second][0]
			cmpd[2]=compound[second][1]
			k1=compound[second][2]
			acidk=0
		}
		else{
			cmpd[0]=compound[second][1]
			cmpd[2]=compound[second][0]
			k1=1e-14/compound[second][2]
			acidk=1
		}
	}
	thereaction=cmpd[0]+" + "+cmpd[1]+" => "	+cmpd[2]+" + "+cmpd[3]
	K=k1*k2/1e-14
	showK[0]=number(k1,2,2)
	showK[1]=number(k2,2,2)
	showK[2]=number(K,2,2)
	buildquestion(option,first,second)
}	
function buildquestion(){
	thequest="Calculate the value of the equilibrium constant for the following proton transfer reaction:<br>"+thereaction
	showquest(thequest)
	buildanswer()
}
function buildanswer(){
	theanswer="K<SUB>rxn</SUB>=K<SUB>a</SUB>*K<SUB>b</SUB>/K<SUB>w</SUB><br>In this case,<br>"
	if(option==1){
	theanswer+=("K<SUB>a</SUB> for "+cmpd[0]+"="+showK[0])
	theanswer+="<br>"
	basek==0?theanswer+=("K<SUB>b</SUB> for "+cmpd[1]+"="+showK[1]):theanswer+=(cmpd[1]+" is the conjugate base of " + compound[second][0]+". Its Kb=Kw/Ka=1*10<sup>-14</sup>/"+number(compound[second][2],2,2)+"="+showK[1])
	}
	else{
		acidk==0?theanswer+=("K<SUB>a</SUB> for "+cmpd[0]+"="+showK[0]):theanswer+=(cmpd[0]+" is the conjugate acid of " + compound[second][0]+". Its K<SUB>a</SUB>=K<SUB>w</SUB>/K<SUB>b</SUB>=1*10<sup>-14</sup>/"+number(compound[second][2],2,2)+"="+showK[0]);
		theanswer+="<br>"+(cmpd[1]+" is the conjugate base of " + compound[first][0]+". Its K<SUB>b</SUB>=K<SUB>w</SUB>/K<SUB>a</SUB>=1*10<sup>-14</sup>/"+number(compound[first][2],2,2)+"="+showK[1])
	}
	theanswer+="<br>"
	theanswer+=(showK[0]+"*"+showK[1]+"/10<SUP>-14</SUP>="+showK[2])
} 
function answer(ans){
	if(tried==1)alert("You've done this one. Get a new problem.");
	else{
	attempts++
	if(tried==2){totl++
		document.forms[0].total.value=totl
		}
	if(ans>.95*K & ans<1.05*K ){ 
    		document.forms[0].results.value="correct"
    		corrt++
		document.forms[0].correct.value=corrt
		tried=1
	}
	else {document.forms[0].results.value="incorrect"
	tried=2}
}}