dr. el-khouri is a highly trained scientist.o, the first part of the demonstration showed how molecules contract when exposed to cold. they can contract so much, in fact, they can change from one form of matter to another. now, the first one we put in here was... >> clear. >> ...clear. >> oh, my gosh! >> to explain it -- so, since it was in there, can you guys see that liquid? >> liquid. >> so, yeah, there's liquid inside of the balloon, and that's just because, like i said, it was in a negative-320-degrees fahrenheit -- the liquid nitrogen's temperature. those molecules get really, really, really, really close together. >> does it make it actually change phases of matter? >> yeah, exactly. >> so, why is it important for more girls to go into s.t.e.m. fields? >> i think one of the biggest things right now that we need to be aware of is that, within the next 5 to 10 years, the majority of jobs that are going to be available in the market are going to require some level of s.t.e.m. skills. and so it's really critical that we try t