Phoenix (2) - S3-E2
Corrected entry: While Clark is inside the semi-truck being delivered to Morgan Edge and Lionel Luthor he manages to remove the kryponite apparently duct taped to his chest. This cannot be possible since he even a small piece of kryptonite (Lana's necklace) was enough for him to trip and fall from several feet away! Imagine a larger chunk like the one they strapped to his chest. He should have been severely weakened by it and the radiation should go through anything in that truck besides lead and the tape used to secure the rock on Clark's chest is not made of lead. His ability to not only have the strength to rip the taped rock off his chest but to then launch it to the far side of the truck should not be possible in view of the nearly immobilizing effects kryptonite has on Clark.
Correction: Seeing all of the times that Clark has been exposed to kryptonite on Smallville, I've made a simple observation. Kryptonite does not take away all of Clark's strength. Rather, it makes him about 1/4 to 1/2 as strong as a normal person of his build. He is still able to perform some physical things, like throwing a rock (which can be seen in the Season 1 Episode 3, Hothead, when he chucks several kryptonite stones at a glass window and breaks it with the impact). There's no accurate way of measuring the pain that he endures from kryptonite, but his physical strength is somewhere along those lines. Therefore, although it would, of course, be painful, he still has enough strength (possibly after getting used to the pain) to be able to pull off the duct tape and throw the kryptonite away from him.
Knever