Why are the out planets mostly composed with ice and gas?

The outer planets, often referred to as gas giants and ice giants, are primarily composed of gases and ices due to their formation in the colder regions of the solar system, where volatile compounds like water, ammonia, and methane could condense. Their significant distance from the Sun allowed them to accumulate large amounts of these lighter materials, while their strong gravitational fields enabled them to retain thick atmospheres. Additionally, their formation involved the accumulation of ices and gases in the protoplanetary disk, leading to the distinct composition observed today.