JQuery :: Usage Of Animate - Elements First Disappear Then Display

I have a list for example
<ul id="applications">
<li id="id-1" class="util"></li>
<li id="id-1" class="app"></li>
<li id="id-1" class="util"></li>
<li id="id-1" class="app"></li>
</ul>

Then I want a select some of the list with some animate effect, first the all of the elements would disappear, then the elements that I wanted would display one by one the code:
$('#applications li').each(function (index) {
setTimeout(function (e) {
e.hide("slow");
}, index * 100, $(this));
});
$('#applications li[class="app"]').each(function (index) {
setTimeout(function (e) {
e.fadeIn("fast");
}, index * 100, $(this));
});

The final effect is that all the elements would disappear first but the element I wanted would not display? Then I think about the queue,before I use it I change a little about the code:
$('#applications li').each(function (index) {
setTimeout(function (e) {
e.hide("slow");
}, index * 100, $(this));
});
$('#applications li')
.each(function (index) {
setTimeout(function (e) {
e.fadeIn("fast");
}, index * 100, $(this));
});

The yellow part is the different from the former one, the effect is that all the elements would disappear first, then all the would display again without any problem!