The seasonal polar caps which appear and disappear with the seasons on Mars are made of
A) methane ice
B) carbon dioxide ice
C) water ice
D) a uniform mixture of water and carbon dioxide ices

Question

Quizplus · Accepted Answer

The seasonal polar caps on Mars are mainly composed of carbon dioxide ice, also known as dry ice. The carbon dioxide in the atmosphere freezes out onto the polar regions during Mars' winter season, and sublimates back into the atmosphere during the summer. While there is also water ice present in the polar caps, it is a minor component compared to the carbon dioxide. Therefore, choice B is the correct answer.

The Seasonal Polar Caps Which Appear and Disappear with the Seasons