<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>userbinator</author><text>&lt;i&gt;Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen.&lt;/i&gt;&lt;p&gt;Which plastics? The most common ones, polyethylene and polypropylene, which this method is designed to process, are entirely hydrogen and carbon, with no double bonds. I don&amp;#x27;t dispute that additional hydrogen is necessary to crack  the polymers into shorter ones, but your description of plastics does not seem to be completely correct.</text><parent_chain><item><author>HackOfAllTrades</author><text>Why do people keep falling for this?  This same fraud used to pop up only every 10 years.  Now it&amp;#x27;s 5 or less.&lt;p&gt;I&amp;#x27;m a PhD chemist.  Please consider this: While plastics and oil are both hydrocarbons they have this important difference.  Liquid hydrocarbons have short carbon chains and lots of hydrogen.  Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen.&lt;p&gt;That is why, when you heat plastic it decomposes into char -- as in charcoal.  It is IMPOSSIBLE to produce oil, even theoretically, without adding a source of hydrogen.&lt;p&gt;A few centuries ago these same fraudsters would be selling you a way to change Iron into Gold.</text></item></parent_chain></comment><story><title>Plastic to Oil – Produces 80% Oil</title><url>https://blest.co.jp/eng/service/be-h/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>cal85</author><text>Interesting, thanks. As someone with little understanding of chemistry, can you clarify why &amp;quot;adding a source of hydrogen&amp;quot; is not possible&amp;#x2F;practical?</text><parent_chain><item><author>HackOfAllTrades</author><text>Why do people keep falling for this?  This same fraud used to pop up only every 10 years.  Now it&amp;#x27;s 5 or less.&lt;p&gt;I&amp;#x27;m a PhD chemist.  Please consider this: While plastics and oil are both hydrocarbons they have this important difference.  Liquid hydrocarbons have short carbon chains and lots of hydrogen.  Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen.&lt;p&gt;That is why, when you heat plastic it decomposes into char -- as in charcoal.  It is IMPOSSIBLE to produce oil, even theoretically, without adding a source of hydrogen.&lt;p&gt;A few centuries ago these same fraudsters would be selling you a way to change Iron into Gold.</text></item></parent_chain></comment><story><title>Plastic to Oil – Produces 80% Oil</title><url>https://blest.co.jp/eng/service/be-h/</url></story>