chemistry

posted by .

15. On October 21, 1982, the Bureau if
the Mint changed the composition of
pennies. Instead of an alloy of 95% Cu
and 5% Zn by mass, a core of 99.2 Zn
and 0.8% Cu with a thin shell of copper
was adopted. The overall composition of
the new penny was 97.6% Zn and 2.4%
Cu by mass. Assume the volume of the
individual metals that make up each
penny can be added together to give the
overall volume of the penny, and assume
each penny is the same size. (Density of
Cu = 8.96 g/cm3; density of Zn = 7.14
g/cm3) Does this account for the
difference in mass among the pennies?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chem

    Final question.. An alloy used in aircraft construction consists of aluminium, copper and magnesium. An 11.34g sample of alloy was treated with alkali to dissolve the aluminium, leaving a residue of mass 2.73g. This residue was treated …
  2. Science

    My physical science class is doing an experiment on the mass of pennies. I hypothesized that newer pennies would have less mass because cheaper materials are being used. I found that before 1982, pennies were made from 95% copper/5% …
  3. Chemistry

    Before 1982 U.S pennies were made of solid copper. As the price of copper rose,the U.S mint switched to a composition that is 97.5% zinc and 2.5% copper. A penny minted after 1982 is 19 mm in diameter and 1.6 mm thick. What is the …
  4. physics

    A racquetball with a diameter of 5.6 cm and a mass of 42 g is cut in half to make a boat for American pennies made after 1982. The mass and volume of an American penny made after 1982 are 2.5 g and 0.36 cm3. How many pennies can be …
  5. physics

    A hollow rubber ball with a diameter of 5.57 cm and a mass of 38.9 g is cut in half to make a boat (in a bathtub) for American pennies made after 1982. The mass and volume of an American penny made after 1982 are 2.5 g and 0.36 cm3. …
  6. physics

    A hollow rubber ball with a diameter of 5.57 cm and a mass of 38.9 g is cut in half to make a boat (in a bathtub) for American pennies made after 1982. The mass and volume of an American penny made after 1982 are 2.5 g and 0.36 cm3. …
  7. physics

    A hollow rubber ball with a diameter of 5.57 cm and a mass of 38.9 g is cut in half to make a boat (in a bathtub) for American pennies made after 1982. The mass and volume of an American penny made after 1982 are 2.5 g and 0.36 cm3. …
  8. astronomy

    Using the densities below, find what percentage of the Earth's mass is contained in its core. If Earth's core were adjusted in radius so that the core contained forty percent of the mass, by what factor would the radius of the Earth …
  9. Chemistry

    How are a mix of pre-1982 and post-1982 pennies a misleading or incorrect analogy for actual element isotopes?
  10. Physics gravity

    A thin spherical shell has a radius of 2.4 m and a mass of 410 kg, and its center is located at the origin of a coordinate system. Another spherical shell with a radius of 1 m and mass 135 kg is inside the larger shell with its center …

More Similar Questions