No it's not. Cyclopentasiloxane's molecular structure is C10H30O5Si5.
Cyclopentasiloxane is a silicone compound and used as an emollient in skin cream products. This ingredient has been noted as having a low risk of cancer.
It provides hair with extra shine without the greasy look.
I do not believe that cyclopentasiloxane is bad for your hair. Case in point, I've been using conditioners that specifically include this ingredient because it conditions THE BEST and leaves absolutely no knots in my hair. Only a little bit of conditioner is necessary when using this ingredient as it spreads so easily that a tiny bit is all you need and you never ever have to leave it in your hair for any amount of time for the conditioner to work! My hair comes out soft, manageable and shiny. Problem is, you won't find this ingredient in less expensive products (Suave doesn't include it in their products as far as I know).
It is an element.
Element
Metal is not an element. It is a term used to classify an element, but it is not an element.
A property of that element. An unstable element. A radioactive element
While different brands of gels have slight variations in ingredients, all hair gels and sprays include complex polymers, water, alchohol, aminomethyl propanol, sodium benzoate, Cyclopentasiloxane (a volitile silicone), and Sodium PCA.
element. Sulfur dioxide (SO2) is a compound
There is no such thing as a good element or a bad element.
5th element - boron 6th element - carbon 7th element - nitrogen 8th element - oxygen 9th element - fluorine 10th element - neon
element = element (אלמנט). If you're asking about an element as in the Periodic Table, then an element in Hebrew is yesod.