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Amiraneli [1.4K]

2 years ago

5

In the video, the water level was 15 milliliters before adding the chain, and 20 milliliters after adding the chain. When I weig

hed the chain, its mass was 76.3 grams.
I believe the chain is solid metal (not gold plated), but is probably a blend of gold and other metals. I looked up that gold has a density of 19.3 g/ml, while the other metals like silver and copper usually blended with gold have a combined density of about 9.7 g/ml.

Determine what percentage of the chain is gold, by mass, to at least 1 decimal place?

2 answers:

BartSMP [9]2 years ago

6 0

345 g / ml I hope this helps you !

beks73 [17]2 years ago

3 0

Answer:39.7%

Step-by-step explanation:

1. First find the density of your chain

Density = mass / volume

Volume = displaced water volume

= Volume of Final level of water - initial level of water

= 20 ml - 15 ml = 5 ml

Mass = 66.7 g

Density = 66.7g / 5 ml = 13.34 g/ml

2. Second, write the denisty of the chain as the weighted average of the densities of the other metals:

Mass of gold × density of gold + mass of other metals × density of other metals, all divided by the mass of the chain.

Calling x the amount of gold, then the amount of other metals is 66.7 - x:

Then, there are 26.47 grams of gold in 66.7 grams of chain, which yields a percentage of:

(26.47 / 66.7) × 100 = 39.7%1. First find the density of your chain

Density = mass / volume

Volume = displaced water volume

= Volume of Final level of water - initial level of water

= 20 ml - 15 ml = 5 ml

Mass = 66.7 g

Density = 66.7g / 5 ml = 13.34 g/ml

2. Second, write the denisty of the chain as the weighted average of the densities of the other metals:

Mass of gold × density of gold + mass of other metals × density of other metals, all divided by the mass of the chain.

Calling x the amount of gold, then the amount of other metals is 66.7 - x:

Then, there are 26.47 grams of gold in 66.7 grams of chain, which yields a percentage of:

(26.47 / 66.7) × 100 = 39.7%

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