Put below code to the footer

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script type="text/javascript">
var a_idx = 0;
jQuery(document).ready(function($) {
$("body").click(function(e) {
var a = new Array("H", "He", "Li", "Be", "B", "C", "N" ,"O", "F", "Ne", "Na", "Mg","Al","Si");
var $i = $("<span/>").text(a[a_idx]);
a_idx = (a_idx + 1) % a.length;
var x = e.pageX,
y = e.pageY;
$i.css({
"z-index": 999999999999999999999999999999999999999999999999999999999999999999999,
"top": y - 20,
"left": x,
"position": "absolute",
"font-weight": "bold",
"color": "#808080"
});
$("body").append($i);
$i.animate({
"top": y - 180,
"opacity": 0
},
1500,
function() {
$i.remove();
});
});
});
</script>