Someone Wants to Sell You a Piece of Gold That

question 15

Multiple Choice

Someone wants to sell you a piece of gold that they say is nearly pure. Before buying the piece, you measure its mass to be 52.3 grams and you find that it displaces 4.16 mL of water. Calculate its density and assess its purity given the fact that pure gold has a density of 19.3 g/mL.

• A)The piece of gold is about 65 percent pure.
• B)The piece of gold is only about 12.6 percent pure.
• C)The piece of gold is only about 8 percent pure.
• D)Not enough information is given to calculate the purity, but enough information is given to let you know that the piece is far from pure.

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Definitions:

Crustaceans

A diverse group of aquatic animals that have a hard exoskeleton, including species such as crabs, lobsters, and shrimps.

Mollusks

A large and diverse phylum of invertebrates that includes snails, slugs, oysters, and octopuses, with a soft body and, frequently, a calcium carbonate shell.

Notochord

A flexible rod made out of a material similar to cartilage that provides support in the embryonic stages of all chordates and some adult animals.

Phylum

A major category in the classification of living organisms, ranking above class and below kingdom.