I bought a scale to measure very small quantities in 0.01 increments.
The scale has a calibration weight of 50 grams and it measures so +/- an error as expected.
My intention for the scale is to measure powder/herbs.
To try it I have a measuring spoon that says 1.25 ml and I used cinnamon as a sample and scooped it, use a knife to flat out the top and when I weighed it the scale reported 0.5 grams while I was expecting 1.25 grams.
I tried with regular sugar (not powedered) and the weight reported is the same as the measuring spoon e.g. for 2.5 ml the scale reports 2.5 grams etc.
So now I am confused. Is there a difference when using powder and measuring spoons? What's the issue here?
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Jim
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I think you are mixing up volume and weight.
Your spoon is measuring a volume, giving you ml of the substance that you scooped. To convert this volume into a mass, you need to multiply it by the substance density in mg/ml.
Additionally, powders and coarse materials like ground herbs will not have a constant density, because of the empty spaces between their parts, which change with how you pour/scoop them.
Try shaking a container filled to the edge with herbs, and see how the level seems to diminish as the herb fragments pack better.
If you want to carefully measure weight for loose substances like powders or ground material, use a scale, not a spoon.
As a reference for how big this effect can be, I routinely store my muesli in a glass jar. By directly putting the muesli in the jar, about 10% remains in the bag. After gently shacking the jar, the whole content can fit in.
L.Dutch
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Volume and weight are two different measurements, a spoon of powder won't weigh as much as a spoon of oil as they have different densities.
However, a handy thing to keep in mind is that with the metric system 1 gram of water = 1ml in standard conditions. So, a flat spoon of water at 1.25ml will weigh 1.25 grams. As long as your scale measures that accurately then it is correct.
