Suppose an element has two naturally occurring isotopes 42
X
20

44
X
20
with atomic masses 42.00 amu and 45.00 amu, respectively. Determine the percent abundance of the
45
X
20
isotope given an average atomic mass of 43.22 amu.

Upon decomposition, one sample of magnesium fluoride produced 1.65 kg of magnesium and 2.56 kg of fluorine. a second sample produced 1.32 kg of magnesium. part a how much fluorine (in grams) did the second sample produce?

What is the typical rotational frequency frot for a molecule like n2 at room temperature (25∘c)? assume that d for this molecule is 1å=10−10m. take the total mass of an n2 molecule to be mn2=4.65×10−26kg. you will need to account for rotations around two axes (not just one) to find the correct frequency. express frot numerically in hertz, to three significant figures.

Which method would be best to separate a mixture of sand and gravel