11. In CBr4, the C-Br bonds are? 1) pure covalent;
2) polar covalent;
3) ionic;
4) coordinate covalent;

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?