# Questions of density and volume

In my lab I determined volumes for two unknown metals by two different methods (displacement in a liquid: V=9ml vs. calculation of all sides: V=8.83 cm3

V=5ml V=4.75 cm3

The volumes are not the same. Which do you believe to be more accurate? Why?

2. What effect a higher erroneous volume of unknown will have on dessity determination? (will the object appear to be denser?, less dense?)

3. I also have two different densities obtained by two different methods:

A) displacement in a water D=9.2g/ml (for one unknown metal) and

D= 10.1 g/ml (for another unknown metal)

B) calculation of all sides: D= 9.4 g/cm3

D= 10.6 g/cm3

They not a same. Is this to be expected considering the volume values I obtained?

4. Is it possible for two different elements to have the same volumes and densities but different masses? Why?

5. If you were asked to find the density of a paper clip made of iron, which method of volume measurement would you use, displacement in a liquid vs. measurement and calculation of all sides? Why?

#### Solution Preview

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2. What effect a higher erroneous volume of unknown will have on dessity determination? (will the object appear to be denser?, less dense?)

density (d) is defined as the mass (M) per unit volume (V):

d = M/V

Thus, an increase in the volume will cause a decrease in the density (the object will appear to be less dense).

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3. I also have two different densities obtained by two different methods:

A) displacement in a water D=9.2g/ml (for one unknown metal) and

D= 10.1 g/ml (for another unknown metal)

B) calculation of all sides: D= 9.4 g/cm3

D= 10.6 ...

#### Solution Summary

This solution gives step by step explanations for various questions involving density and volume.