SOLUTION: An alloy was machined into a flat disk, 31.5mm in diameter and 4.5mm thick, with a hole 7.5mm in diameter drilled through the center. The disk weighed 20.2g. What is the density of

Question 1145501: An alloy was machined into a flat disk, 31.5mm in diameter and 4.5mm thick, with a hole 7.5mm in diameter drilled through the center. The disk weighed 20.2g. What is the density of the alloy?
I'm an honors chem student. Can you help me learn to solve problems like these???
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
An alloy was machined into a flat disk, 31.5mm in diameter and 4.5mm thick, with a hole 7.5mm in diameter drilled through the center. The disk weighed 20.2g. What is the density of the alloy?
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Find the volume. I would use cc, cubit cms, not cubic mms.
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Divide the grams by the volume ---> gms/cc (density)
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How did you get to be an "honors student?"
You don't seem to know basic stuff.

Answer by ikleyn(52835) (Show Source): You can put this solution on YOUR website!
.

The volume of the original flat disk (cylinder) before drilling the hole is = cubic centimeters. The volume of the hole is cubic centimeters. The volume of the metal is the difference. Divide 20.2 grams by the volume of the metal. In this way, you will obtain the density of the alloy in grams per cubic centimeters.

Happy calculation (!)

Is everything clear to you in my instructions ?

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