Define atomic mass. What is its unit?

Estimate the mass, in whole numbers, of each isotope.

4.  Estimate the mass, in whole numbers, of each isotope.

a)  phosphorus-31

b)  carbon-14

c)  americium-241

5. Determine the atomic mass of each element, given the isotopic composition.

a)  lithium, which is 92.4% lithium-7 (mass 7.016 u) and 7.60% lithium-6 (mass 6.015 u)

b)  oxygen, which is 99.76% oxygen-16 (mass 15.995 u), 0.038% oxygen-17 (mass 16.999 u), and 0.205% oxygen-18 (mass 17.999 u)

6.  Determine the atomic mass of each element, given the isotopic composition.

a)  neon, which is 90.48% neon-20 (mass 19.992 u), 0.27% neon-21 (mass 20.994 u), and 9.25% neon-22 (mass 21.991 u)

b) uranium, which is 99.27% uranium-238 (mass 238.051 u) and 0.720% uranium-235 (mass 235.044 u)

7.  How far off would your answer be from Exercise 5a if you used whole-number masses for individual isotopes of lithium?

8.  How far off would your answer be from Exercise 6b if you used whole-number masses for individual isotopes of uranium?

9.  What is the atomic mass of an oxygen atom?

10.  What is the molecular mass of oxygen in its elemental form?

11.  What is the atomic mass of bromine?

12.  What is the molecular mass of bromine in its elemental form?

13.  Determine the mass of each substance.

a)  F₂

b)  CO

c)  CO₂

14.  Determine the mass of each substance.

a)  Kr

b)  KrF₄

c)  PF₅

15.  Determine the mass of each substance.

a)  Na

b)  B₂O₃

c)  S₂Cl₂

16.  Determine the mass of each substance.

a)  IBr₃

b)  N₂O₅

c)  CCl₄

17.  Determine the mass of each substance.

a)  GeO₂

b)  IF₃

c)  XeF₆

18.  Determine the mass of each substance.

a)  NO

b)  N₂O₄

c)  Ca