What cause thunder to occur? Thunder is caused by . When a lightning bolt travels from the cloud to the ground it actually opens up a little in the air, called a .

Lightning

Hole

Channel

Explanation:

Thunder usually occurs as a result of the occurence of lightning. When lightening occurs, temperature raised around it to 5times of the heat of the suns.This change of temperature that happens violently leads to or makes sound that makes or causes the oxygen burn up.The air as a result rushes to fill the gap that had no oxygen. With this sudden movement, a sound is created and this is what makes the thunder. It is said that about 70% of thunder occurs over land in the tropics where there is said to be where unstable atmospheres are the greatest.

mercury

explanation:

mercury is the least dense because of its size