Principle Of The Density Determination; Density Determination Of Solids; Fundamentals - Mettler Toledo Excellence XP Bedienungsanleitung

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Principle of the density determination

The density ρ ρ ρ ρ ρ is the quotient of the mass m and the volume V .
m
ρ
=
V
The international system of units specifies kg/m
to lab purposes.
Density determinations are frequently performed by Archimedes' principle, which is also used with the
density determination kit for the balances. This principle states that every solid body immersed in a fluid
apparently loses weight by an amount equal to that of the fluid it displaces.
The procedure for the density determination by Archimedes' principle depends on whether the density of
solids or liquids has to be determined.
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Density determination of solids

4.1

Fundamentals

The density of a solid is determined with the aid of a liquid whose density ρ
are usually used as auxiliary liquids). The solid is weighed in air ( A ) and then in the auxiliary liquid ( B ).
The density ρ can be calculated from the two weighings as follows:
A
ρ
Density: =
A-B
A-B
α
V
Volume: =
ρ - ρ
0
Density determination kit for Excellence XP/XS precision balances
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ρ = Density of sample
- ρ )+ ρ
(ρ
A = Weight of sample in air
0 L L
B = Weight of sample in the auxiliary liquid
ρ
ρ
L
α = Balance correction factor (0.99985), takes air
as the unit of density. However, the unit g/cm
= Density of the auxiliary liquid
0
= Air density (0.0012 g/cm
L
buoyancy of the adjustment weight into account.
is better suited
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is known (water or ethanol
0
)
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