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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: OfficialAnu on September 04, 2019, 07:22:04 PM

Title: In HPLC, why are mixtures in a certain ratio?
Post by: OfficialAnu on September 04, 2019, 07:22:04 PM
For example, to separate two similarly polar molecules such as water and 1-pentanol, why is the mixture in a ratio (ex. 70:30)? How does this create more visible separation?
Title: Re: In HPLC, why are mixtures in a certain ratio?
Post by: jeffmoonchop on September 04, 2019, 11:36:56 PM
Water is way more polar than pentanol. Not sure what you're asking about the ratios though. With HPLC, you can calculate the quantity of each in a mixture. So if it's 70:30, then its because someone made a mixture of 70:30 water: pentanol. I should also note that pentanol is not miscible with water so you actually wouldn't be able to make a mixture without some additives.