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kenny6666 [7]
2 years ago
8

Sterling silver is 92.5% silver and 7.5% copper. Its density is 10.25 g/cm3. A sterling silver pendant is added to a graduated c

ylinder filled with 50.0 mL of water. The volume rises to 61.3 mL. What is the mass of copper contained in this pendant?
Chemistry
1 answer:
Mariulka [41]2 years ago
4 0

From the information given:

  • The volume of the graduated cylinder = 50.0 mL
  • when a sterling silver pendant is added, the volume increases to = 61.3 mL

∴

The volume of the sterling silver pendant is:

= 61.3 mL - 50.0 mL

= 11.3 mL

Since, 1 mL = 1cm³

Then;

11.3 mL = 11.3 cm³

  • the density of the sterling silver = 10.25 g/cm³

Using the relation for Density; i.e.

\mathbf{Density = \dfrac{mass}{volume}}

\mathbf{10.25 \ g/cm^3= \dfrac{mass}{11.3  \ cm^3}}

mass = 10.25 g/cm³× 11.3 cm³

mass of the sterling silver = 115.825 grams

Recall that sterling silver has:

  • 92.5% silver and;
  • 7.5% copper

∴

The mass of the copper contained in the sterling silver pendant can be calculated as:

\mathbf{= \dfrac{115.825  \ g \times 7.5}{100}}

= 8.687 grams

Therefore, we can conclude that the mass of the copper contained in the sterling silver pendant is 8.687 grams

Learn more about the relation between Density, Mass, and Volume here:

brainly.com/question/24386693?referrer=searchResults

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