It depends The answer is "it depends."
If we don't know what the teaspoon is holding, then we can't answer the question. That's because a milligram is a unit of WEIGHT, whereas a teaspoon is a unit of volume.
So what? you ask. Well, a teaspoon of black pepper will not weigh the same as a teaspoon of iron filings, which will have a different weight than a teaspoon of sugar, which will have a different weight than a teaspoon of tungsten filings or liquid Mercury.
Do not confuse WEIGHT with VOLUME.
For example, a level teaspoon of table salt has (weighs) about 2300 milligrams. FYI, the recommended daily allowance (RDA) is 2400 milligrams. And average consumption in the USA is 3500 milligrams. Drop the dill pickle and back away!
There are 10 milligrams in one teaspoon.
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The teaspoon as a volume unit has 5 mL.
Mass = volume x density; density is a specific characteristic of any material. So the mass contained in a teaspoon depends on the density.
There are about 5 milliliters in a teaspoon.
There are approximately 0.05 teaspoons in one fourth milliliter (ml).
167.58 ml 1 milliliter equals 0.202 US teaspoons. 1 teaspoon is 4.92 milliliters
There are approximately 2.3 teaspoons in 11.5 milliliters.
152.16 tsp 1 milliliter equals 0.202 US teaspoons. 1 teaspoon is 4.928 milliliters
9 metric teaspoons
That is approximately 5.9 teaspoons
375 mL = about 76.08 US teaspoons.
100 mL = about 20.3 US teaspoons.
32 US teaspoons = about 157.725 mL
0.9 mL = about 0.18 US teaspoons.
That is approximately 100 teaspoons
10.14 tsp
a teaspoon is approximately 5 ml, and tablespoon 25
There are about 5 milliliters in a teaspoon.
There are 15 ml in 3 teaspoons, therefore there would be 10 mL's in 2 teaspoons.
Six teaspoons is about 29.57 ml