Very small crystals composed of 1000 to 100,000 atoms, called quantum dots, are being investigated for use in electronic devices.
(a) Calculate the mass in grams of a quantum dot consisting of 1.400 104 atoms of silicon.
(b) Assuming that the silicon in the dot has a density of 2.3 g/cm3, calculate its volume.
(c) Assuming that the dot has the shape of a cube, calculate the length of each edge of the cube.

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asked by Anita
  1. How many moles Si in the dot?
    1.400 x 10^4 atoms/6.022 x 10^23 = ??moles.
    Convert that to grams.
    ?? moles x molar mass Si = grams.

    #2. mass = volume x density.
    You have mass and density, calculate volume.

    3. volume = length^3; calculate length.
    Post your work if you get stuck.

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    posted by DrBob222

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