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General Category => General Homebrew Discussion => Topic started by: curtdogg on January 25, 2016, 04:40:21 AM

Title: Specific gravity.
Post by: curtdogg on January 25, 2016, 04:40:21 AM
Please recommend some good easy to read articles on gravity and what it is.
The more I learn the more complicated it seems.

R,
Curtdogg
Title: Specific gravity.
Post by: Stevie on January 25, 2016, 04:42:16 AM
Density of a liquid as compared to pure water. It's not that complicated.

https://en.m.wikipedia.org/wiki/Specific_gravity

Honestly, I have more trouble with mass vs weight.
Title: Re: Specific gravity.
Post by: Bob357 on January 25, 2016, 05:47:48 AM
https://en.wikipedia.org/wiki/Specific_gravity

Title: Re: Specific gravity.
Post by: pete b on January 25, 2016, 12:49:21 PM
While its good to know the underlying science, what is more important is learning how its used by brewers. For instance knowing that when gravity stops changing fermentation is done or stuck. After using it for awhile it becomes a second language and you will find yourself wanting to make an IPA that starts at 1.060 and finishes around 1.015 or a saison that starts at 1.050 and finishes at 1.007 and choosing your yeast and manipulating the fermentability of your wort accordingly.
Title: Re: Specific gravity.
Post by: dunngood on January 26, 2016, 03:03:29 AM
One point to remember about PH is 5.0 is 10x more acidic than 6.0. But because PH is logarithmic,  5.0 is 100x more acidic that 7.0+