var met = new Array();
var activ = new Array();
var i = 1;
var query = "";
var catAns = 0;
var anAns = 0;
var postring = "A724613859";
var catconc = 0;
var anconc = 0;
var qnumber = parent.qnum;
var myanswer = 0;
var picked = "";





for (i==1;i<10;i++){
	met[i] = parent.BB.metal[i].E;
	}
	
function QQ(){
if (qnumber == 0){
	Q0();
	}
if (qnumber == 1){
		 Q1();
		parent.BB.prepQuestion();
		}
if (qnumber == 2){
	 Q2();
	}
if (qnumber == 3) Q3();
if (qnumber == 4) Q4();
if (qnumber == 5) Q5();
if (qnumber == 6) Q6();
	
	}

function Q0(){
	query = "Prepare cells with different electrodes and concentrations and measure their voltages."
	//parent.AA.cover();
	//parent.CC.cover();
	}
	
	
function Q4(){
parent.BB.newUnknown();
query = "Problem: Determine the standard reduction potential (<font color = '#000000'><i>E<sup>o</sup></i></font>) for <font color = '#000000'>Wd(s)/Wd<sup>2+</sup>(aq)</font>.";
}

function Q5(){
parent.BB.newUnknown();
query = "Problem: Estimate the <font color = '#000000'>mean ionic activity coefficient</font> for <font color = '#000000'> 1.00 Molar Wd(NO<sub>3</sub>)<sub>2</sub>(aq).</font>";
myanswer = parent.BB.gamma(9,1);

}

function pickMe(aa){
	var who = "P" + aa;
	var bb = 10 + 1*aa;
	var which = "";
	var where = "";
	var nm = parent.BB.metal[bb].sym.substring(0,2);

	if (picked != ""){
		which = "P" + (picked - 10);
		where = parent.BB.metal[picked].sym.substring(0,2);
		eval('document.' + which + '.src = "' + where + '.gif"');
		}
	picked = bb;	
	eval('document.' + who + '.src = "spc.gif"');

	}
	
	function repMe(aa){
	var who = "S" + aa;
	var nm = "";
	var which = "";
	var where = "";
	var bb = 0;
	if (activ[aa] > 0){
	bb = 10 + activ[aa];
	which = "P" + activ[aa];
		where = parent.BB.metal[bb].sym.substring(0,2);
		eval('document.' + which + '.src = "' + where + '.gif"');
	eval('document.' + who + '.src = "spc.gif"');
	activ[aa] = 0;
	}
	if (picked != ""){
	nm = parent.BB.metal[picked].sym.substring(0,2);
	eval('document.' + who + '.src = "' + nm + '.gif"');
	activ[aa] = picked - 10;
	picked = "";
	}

	}
	
function Q6(){
var i = 1;
var j = 0;
var who = ""
query = 'Arrange the metal electrodes in order of decreasing electrochemical activity.<BR>';
query += 'Click on the symbol of a metal, then on its position in the activity series.<BR>';
for (i==1;i<6;i++){
	j = 10 + i;
who = parent.BB.metal[j].sym;
who = who.substring(0,2) + ".gif";
	query += '<img src = ' + who + ' name = "P' + i + '" border = "0" height = "20" width = "20" onClick= "pickMe(' + i + ');return false;">';

	if (i < 5) query += '<img src = "spc.gif" border="0" height = "20" width= "42">';
}
query += "<BR>Most Active&nbsp;&nbsp;&nbsp;&nbsp;";
i = 1;
for (i==1; i<6;i++){
	query += '<img src= "spc.gif" name = "S' + i + '" border = "1" height = "20" width = "20" onClick = "repMe(' + i + ');return false">';
	if (i < 5) query += "&nbsp;&nbsp;&nbsp;&nbsp;>&nbsp;&nbsp;&nbsp;&nbsp;";
	}
query += '&nbsp;&nbsp;&nbsp;&nbsp;Least Active';
}

function Q1(){
var dummy = 0;
var cc = 0;
catAns = Math.round(0.5 + 8*Math.random());
	anAns = Math.round(0.5 + 8*Math.random());	
	while (anAns == catAns) anAns = Math.round(0.5 + 8*Math.random());
		if (met[catAns] < met[anAns]){
		dummy = catAns;
		catAns = anAns;
		anAns = dummy;
		}
	 cc = Math.round(1000*(met[catAns] - met[anAns])).toString();
	 while (cc.length < 4) cc = "0" + cc;
	 cc = cc.charAt(0) + "." + cc.substring(1);
	 query = 'Problem:  Construct a cell with with the ANODE on the Left and <font color = "#000000"><i>E<sup>o</sup></i> = ' + cc + ' V.</font>';
	// parent.AA.cover();
	// parent.CC.cover();
}

function Q2(){
var dummy = 0;
var cc = 0;

	catAns = Math.round(0.5 + 8*Math.random());
	anAns = Math.round(0.5 + 8*Math.random());
	while (anAns == catAns) anAns = Math.round(0.5 + 8*Math.random());
	if (met[catAns] < met[anAns]){
		dummy = catAns;
		catAns = anAns;
		anAns = dummy;
		}
	parent.BB.Anion = anAns;
	parent.BB.Cation = catAns;
	parent.top.BB.getName(anAns,1);
	parent.top.BB.getName(catAns,2);
	i = postring.charAt(anAns);
	parent.top.AA.document.AForm.an.selectedIndex = i;
	parent.top.AA.document.AForm.anS.selectedIndex = i;
	i = postring.charAt(catAns);
	parent.top.CC.document.AForm.an.selectedIndex = i;
	parent.top.CC.document.AForm.catS.selectedIndex = i;
	
	myanswer = met[catAns] - met[anAns];
			parent.BB.Cathode = catAns;
		parent.BB.Anode = anAns;
		parent.BB.colorwater(1);
		parent.BB.colorwater(2);
	anconc = "0.0001";
	catconc = "0.0001";
	if (catAns == 1){
		anconc = "1.00";
		catconc = "1.00";
		}
	parent.AA.document.AForm.CA.value = anconc;
	parent.CC.document.AForm.AC.value = catconc;
	
	
	 query = "Problem:  Calculate <font color = '#000000'><i>E<sup>o</sup></i></font> for this cell.";
	 //parent.AA.cover();
	 //parent.CC.cover();
	
	}


function Q3(){

var dummy = 0;
var cc = 0;
var bb = 0;

	catAns = Math.round(0.5 + 8*Math.random());
	anAns = Math.round(0.5 + 8*Math.random());
	//while (anAns == catAns) anAns = Math.round(0.5 + 8*Math.random());//++++++++++
	if (met[catAns] < met[anAns]){
		dummy = catAns;
		catAns = anAns;
		anAns = dummy;
		}
	parent.BB.Anion = anAns;
	parent.BB.Cation = catAns;
			parent.BB.Cathode = catAns;
		parent.BB.Anode = anAns;
		parent.BB.colorwater(1);
		parent.BB.colorwater(2);
	parent.top.BB.getName(anAns,1);
	parent.top.BB.getName(catAns,2);
	i = postring.charAt(anAns);
	parent.top.AA.document.AForm.an.selectedIndex = i;
	parent.top.AA.document.AForm.anS.selectedIndex = i;
	i = postring.charAt(catAns);
	parent.top.CC.document.AForm.an.selectedIndex = i;
	parent.top.CC.document.AForm.catS.selectedIndex = i;
	
	cc = Math.round(-.5 + 5*Math.random());
	dummy = 1;
	if (Math.random() > .5) dummy = 5;
	if ((cc==0) && (dummy == 5)) dummy = 2;
	anconc = dummy*Math.pow(10,-cc);
		cc = Math.round(-.5 + 5*Math.random());
	dummy = 1;
	if (Math.random() > .5) dummy = 5;
	if ((cc==0) && (dummy == 5)) dummy = 2;
	catconc = dummy*Math.pow(10,-cc);
	if (catAns == anAns){
	   	   	dummy = 5;
		bb = Math.random();
		if (bb < .67) dummy = 2;
		if (bb < .33) dummy = 1;
		cc = 3;
		if (Math.random() > .5) cc= 4;
		anconc = dummy*Math.pow(10,-cc);
		dummy = 5;
		bb = Math.random();
		if (bb < .67) dummy = 2;
		if (bb < .33) dummy = 1;
		catconc = dummy;
		if ((dummy == 5) || (Math.random() > .5)) catconc = dummy*Math.pow(10,-1);
	
	}
	parent.CC.document.AForm.AC.value = catconc;
	parent.AA.document.AForm.CA.value = anconc;
	parent.BB.showmeter(3);
	parent.BB.hidemeter();
	parent.BB.cAn = anconc;
	parent.BB.cCat = catconc;
	
	 query = "Problem:  Calculate the expected voltage <font color = '#000000'>(<i>E</i>)</font> of this cell.";
	 //parent.AA.cover();
	 //parent.CC.cover();
	
	
	}