How to calculate displacement from density?

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To calculate displacement from density, start with the density of the powder, which is 1.06 g/cm³. For 1000 mg of this powder, the volume can be calculated using the formula v = m/ρ, resulting in a displacement volume. If the powder is insoluble, the total volume of the mixture will equal the sum of the powder's volume and the liquid's volume. The volume of the filler liquid can be determined by subtracting the powder's volume from the total desired volume. Accurate unit management is crucial throughout the calculation process.
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If this the wrong section to post this, please know that I am very sorry, but I don't know much about any of the things going on, on here so please bare with me.


Say you got some powder, and say this powder has a density of 1.06g/cm3 (or 1.06g/mL, right?).

Now say you want to put 2500mg of this powder in a solvent mixture (made from cottonseed oil, 0.3mL benzyl alcohol and 1.7mL benzyl benzoate), that you want it to be total of 10ml, with the powder being at a concentration of 250mg/mL

How would one go about calculating the displacement caused by this powder, which will then determine how much oil one would need to use?
 
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Simple way of putting it:

Powder has a density of 1.06g/cm3

How much will 1000mg of the powder displace 10ml of water
 
If the powder is completely insoluble, and does not form any kind of compounds with water, then the resultant volume is a simple sum of the volume of the powder and of the liquid.

Otherwise, you will need the properties of the resultant solution/compound.
 
Okay let us say the powder is insoluble, how would one go about calculating thing (I need a formula)
 
Say the concentration is c mg/mL.

Then in volume V ml of the mixture, you will have m = cV mg of the powder.

The density of the powder is ρ mg/mL, so mass m corresponds to volume v = m/ρ mL.

Then the volume of the filler liquid is u = V - v mL.

I am sure you can substitute and simplify the rest. But mind the units!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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