Hello everyone... I am in a university-level science coarse and I am having real trouble with this question on our HW assignment as I am not a math oriented individual.... Any help is greatly appreciated. I know its long, but I am really terrible at this whole math thing.
Their starting point was the assumption that the total mass or iridium in the K/T
layer was equal to the mass of iridium in the original impactor:
Ir(layer) = mIr(impactor)
1) First you must estimate the mass of iridium in the K/T layer. Use the following
a. On average, the iridium layer is
H = 3 cm thick (what is it in SI units?).
b. The density of the K/T layer containing iridium is d = 2.5 g/cm3 (what is it in SI
c. On average, the layer had a concentration of iridium of CIr(layer) =20 parts per
billion (20 ppb) by weight. (Hint: in scientific notation, 1 billion is 109, so 1 ppb is
equivalent to 1/109 or 10-9)
d. Assume that the iridium concentration was uniform around the Earth.
e. The total area of the Earth is AEarth = 4 π×(REarth)2
where the radius of Earth is
REarth = 6378 km (what is it in SI units?).
f. The total mass of the K/T layer, m(layer), is given by the area of the Earth (AEarth)
multiplied by the layer thickness (H) multiplied by the layer density (d).
g. The total mass of iridium in the K/T layer is given by the mass of the layer
multiplied by the iridium concentration:
Ir(layer) = m(layer)×CIr(layer)