The outer planets are mostly formed of lighter elements because these three condense are a<u> lower temperature</u>.
<u>Explanation:</u>
The planets based on the location of the sun is divided into two, that is outer planets and inner planets.
The Outer planet which is far from the sun consists of larger quantity of lighter substances such helium, hydrogen, methane which would condense at the lower temperature. And remains gaseous inside the frost line that would exit far away for the sun so the temperature is low and the lighter materials are easier to condense in lower temperature to form terrestrial rocks.
The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. ... After ice melts into liquid water, you can refreeze it into solid ice if the temperature drops. Freezing and melting are physical changes.