system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: why is wax clear when melted but opaque in a solid form?
gpt
Basically it's caused by crystallization in the wax. Most modern candles and crayons are made from paraffin wax which contain the CnH2n+2 hydrocarbon formula. When solid, these alkyl chains are rigid and align and crystallize. These crystallites scatter light which leads to higher opacity. When heated, the alkyl chains lose their fixed structures and the crystallites melt. the resulting amorphous liquid no longer scatters light.