# Purity and Density of metals

Determination of density has many practical applications. Is a piece of jewelry pure gold or is it an alloy perhaps of gold and silver? Give that the densities of gold and silver at 25 degrees C are 19.3 and 10.5g/mL respectively and that the volume of the alloy is the sum of the volumes of the metals used, calculate the density of an alloy that is 75% by mass gold and 25% silver. (Hint: Assume you have 1.00g of the alloy).

Also, determine the density of an alloy that is 50% by mass gold and 50% silver. If the volume of the jewelry is about 1 mL, could you use your lab balance and graduated cylinder to distinguish between pure gold and the above alloys? Explain your answer.

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Determination of density has many practical applications. Is a piece of jewelry pure gold or is it an alloy perhaps of gold and silver? Give that the densities of gold and silver at 25 degrees C are 19.3 and 10.5g/mL respectively and that the volume of the alloy is the sum of the volumes of the metals used, calculate the density of an alloy that is 75% by mass gold and 25% silver. (Hint: Assume you have 1.00g of the alloy).

If we have one gram of the alloy, it will contain 0.75g gold and 0.25g silver.

Because gold has a density ...

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The solution provides and easy to follow explanation of the concepts and gives all mathematical steps wherever necessary.