   <!-- HIDE FROM OTHER BROWSERS
   var Ans = "XX"
   var corshape = " "
   function setProb()  {

   var drill = new Array("NH3","PCl5","NO3-1","NH4+1","IF5","IF4-1","NO2-1",
   "NO2+1","SiCl4","SiCl6-2","OF2","PCl3","XeF2","XeF4","XeO3","IF2-1",
   "SO2","SO3","SO3-2","SO4-2", "PH3","CHCl3","BrF4-1","BCl3","POCl3",
   "PCl2-1","ClO2-1","XeOF4","SeF4", "SF6","BrF3","CO3-2","CO2","IF4+1",
   "SF5+1","IF6+1","SbF6-1","PBr4+1","CH2Cl2","BH2-1","CF4","CH2O", "XeOF4",
   "BeF2","OO2","NNO","NO2","XeF3-1","PF4-1")

     var num = Math.floor(Math.random()*drill.length)

     //substance parameters: (name,formula,charge,molwt,shape,gamt,chemamt)
     newSub = new substance(" ",drill[num],0,0,0,0,0)
     newSub.parsForm()
     newSub.getShape()
     document.write("<B>What is the shape of " + newSub.fmatForm()+ "?</B>")
   }

   function checkAns(form,Value) {

     var vsShapes = new Array("Bent 109 degrees","Bent 120 degrees","Linear",
           "Octahedron","Planar Triangle","SeeSaw","Square Planar",
           "Square Pyramid","Tetrahedron","Trigonal Bipyramid",
           "Trigonal Pyramid","T-Shaped")
     var vsForms = new Array("AX2E2.gif","AX2E.gif","AX2.gif","AX6.gif",
           "AX3.gif","AX4E.gif","AX4E2.gif","AX5E.gif","AX4.gif","AX5.gif",
           "AX3E.gif","AX3E2.gif")
     var Answer = vsShapes[Value]
     if (Answer == newSub.shape) {
       Ans = "Correct!"
       corshape = vsForms[Value]    
       }
       else {
         Ans = "No - it is " + newSub.shape
         for (var i = 0; i <= 11; i++) {
           if (newSub.shape == vsShapes[i]) {
               corshape = vsForms[i]
               break
           }
         }
       }
       form.feedBack.value = Ans
       parent.toc.document.vshapes.src=corshape
   }

   function newPro() {

      window.open("vsprob1.htm","main")
      parent.toc.document.vshapes.src="vsepr2.gif"
   }
   // STOP HIDING FROM OTHER BROWSERS -->
