Am I calculating this Gravity right?

[solomon1]

I have added 8 kg of sugar to 5 gallons (22.7 litres) of water in order to try and ferment to as close to 20%ABV as possible.

I didnt take an original gravity reading and i am trying to figure out what it would be.

if 0.0003835 is what 1g of sugar adds to 1L of wort,
is it as simple as;
0.0003835 x 8000 (grams of sugar) = 3.068
3.068 / 22.7 (litres of water) = 1.1352

It this right? would really appreciate bit of advice. :)

 

[pittsy]

23 liters with 8kg cane sugar is 1.131 and should ferment to approx 1.033 giving you approx 13.1% , maybe it will ferment lower but thats what hopeville says http://beercalculus.hopville.com/recipe#

 

[Moley]

If you've ADDED 8kg of sugar TO 22.7 litres, sugar bulks up volume by approx. 600ml per kg, so you should now have 22.7 + 4.8 = 27.5 litres of liquid.

8kg in 27.5l = 290g/l = OG 1.104

I can't see that giving you any more than 16% abv.

 

[solomon1]

If you've ADDED 8kg of sugar TO 22.7 litres, sugar bulks up volume by approx. 600ml per kg, so you should now have 22.7 + 4.8 = 27.5 litres of liquid.

Sorry my mistake, in total it is 22.7 litres.
So following your approximation 22.7 - 4.8 = 17.9
meaning it is must be 8kg into 17.9 litres,

do you know what the OG would be for these stats?
possibly would it be;
8000 / 17.9 = 446.9g per l
446.9 x 0.0003835 = 1.171 ??

Thanks for your help. :)

 

[Moley]

No, you need the sugar content and the total volume, so 8kg in 22.7 litres = 352g/litre.

100g/litre gives 36 gravity points (1.036)

352g will therefore give you 3.52 x 36 = 127 points = 1.127

I still don't see where they get 20% abv from, but I don't know what the FG might be.


Scott: What's the theoretical gravity of 80% water + 20% alcohol?

 

[solomon1]

I still don't see where they get 20% abv from, but I don't know what the FG might be.

yeah im finding it hard to work out how its gonna end up as 20%, ill let you know the FG as well.
Cheers