hi welcome to science for skills in this episode we're going to compare the levels of carbon dioxide in inhaled and exhaled air for this experiment we're going to use lime water lime water indicates the presence of carbon dioxide so when there's carbon dioxide present lime water will turn from a clear to a Milky color we have them in a couple of test tubes here one test tube just has a straw going down into lime water the other test tube has two straws in a stopper going into the test tube so uh first of all guys you need goggles on CU you need your eyes to see the results okay in the first test tube I'm going to Exhale into the straw and the straw into the lime water and we'll see the lime water turn [Music] milky now you can see the lime water in this test tube has turned a Milky color and that shows that there's carbon dioxide present in the exhale there now for this test tube I'm going to inhale into the red straw that's going to draw the air through the blue straw down through the lime water and up out the red straw that should mean that only air from outside will pass through the lime water and you can see the lime water d has stayed a clear color so you can see there now the exhale there the lime water has turned a Milky color the inhale there the lime water has stayed clear that shows that there's more carbon dioxide in exhale there than there is in inhale there that's the end of that experiment guys I hope you enjoyed it and I'll see you in the next episode [Music] e