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  #1  
Old 25th August 2009, 04:47 PM
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Smile Measuring chemicals

Hi,
I was wondering if there is a method to measure chemicals when it is a very small quantity. I have a digital scale, but my scale does not give decimals. The weight that I have to measure are 0.2g, 2.2g and 5.5g.
Thank you
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Old 25th August 2009, 04:55 PM
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Get smaller scales?
I have one like this I use for chemical weighing only
http://www.amazon.co.uk/Salter-1250-...dp/B0006MS374/

Alternatively, it depends on what the chemical is and where you're using it, you can dissolve it into solution then portion out the solution into your mix. I'm not very good with maths so I'll let someone more clever than me try to help you there.
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Old 25th August 2009, 04:56 PM
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Jaques

You need to make up a percentage solution

EG - a 10% solution has 10 grams dissolved in 100ml of water or 100g in a litre. So for every 10 ml of the solution that is used in a formula it will always contain 1 gram of the required chemical.
Hope that helps

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Old 25th August 2009, 05:11 PM
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Everyone, thank you. By the way the chemicals are Metol 2.2g, Benzotriazole 0.2 and Pot Brom 5.5.
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Old 25th August 2009, 05:12 PM
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I think this is a very good idea to buy a small scale. I will get one so it will be easier. Thanks Heather.
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Old 25th August 2009, 05:27 PM
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I've got one of the little Salter 'diet' scales that will measure down to 0.1g - accurate enough for most uses. BTW Jacques, what are you brewing?

Rob
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Old 25th August 2009, 05:43 PM
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Be sure to check their calibration with some known weights. I have had electronic scales that were very inaccurate.
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Old 25th August 2009, 05:56 PM
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I am measuring for a one liter on Ansco 130.
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Old 25th August 2009, 06:34 PM
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Jacques, I think if you are doing or planing to do a fair bit of home brew, then investment in an electronic balance with a resolution of at least 0.1 gramme is certainly worthwhile.
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Old 25th August 2009, 06:40 PM
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Thanks everyone, I will buy a scale that provides 0.1 gram increments.
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