Chemistry help please?

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argh.heartbreak.

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Suppose you have two 100 ml graduated cylinders. In each cylinder there is 40.0ml of water. You also have two cubes:one is lead and the other is aluminum. Each cube measures 2.0 cm on each side. After you carefully lower each cube intothe water of its own cylinder, what will the new water level be in each of the cylinders?

the density of lead is 11.3g/ml while aluminum has 2.7g/ml
haha...really? that's all? MAN that was my answer before...and yeah i'm really confused on why they included the densities! haha..thanks alot you'll get the best answer.:D
oh spacean..what if it is wood? how would you calculate it then if the density will affect its volume?
 
They threw the density in there at the end to throw you off because you don't need it for these two materials. The volume of a cube is its side cubed (side*side*side). Therefore the volume of each cube is 2*2*2 which equals 8 cubic centimeters. Cubic centimeters are typically used with solids and milliliters with volume, but they are interchangeable. Since both cubes have the same volume, they will displace the same amount of water regardless of their density. Therefore the new water level in each cylinder will be 40 + 8 which equals 48mL.

Just remember, the only reason this works is because both of the cube materials have a higher density than water and will be completely submerged. However, if one of the materials was less dense, such as wood, it would not completely submerge in the water and would displace less water than its total volume.
 
They threw the density in there at the end to throw you off because you don't need it for these two materials. The volume of a cube is its side cubed (side*side*side). Therefore the volume of each cube is 2*2*2 which equals 8 cubic centimeters. Cubic centimeters are typically used with solids and milliliters with volume, but they are interchangeable. Since both cubes have the same volume, they will displace the same amount of water regardless of their density. Therefore the new water level in each cylinder will be 40 + 8 which equals 48mL.

Just remember, the only reason this works is because both of the cube materials have a higher density than water and will be completely submerged. However, if one of the materials was less dense, such as wood, it would not completely submerge in the water and would displace less water than its total volume.
 
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