UNIT 3 REVIEW WORKSHEET
Part 1 - Fill in the
blanks
Atoms are made up of
electrons, which have a 1 charge;
1. ________________
2 , which have a positive charge; and
3 , which are
neutral. 2. ________________
The latter two particles are found in the 4 of the
atom.
3. ________________
It was 5 who
discovered the nucleus of the atom. The
4. ________________
nucleus has a 6 charge and it occupies a very small
volume 5. ________________
in the atom. In contrast, the negatively-charged 7 occupies
6. ________________
most of the volume of the atom.
7. ________________
The number of 8 in
the nucleus of the atom is the atomic 9
8. ________________
of that element. Because the atom is
electrically neutral,
the
9. ________________
number of protons and 10 are
equal. The sum of the 11
10. ________________
and neutrons is the mass number. Atoms of the same element
are 11.
________________
identical in most respects, but they can differ in the number
of 12. ________________
12 in the nucleus. Atoms
that have the same number of protons 13. ________________
but different mass numbers are called 13 .
The 14 of
an element is the weighted average of the masses
of 14. ________________
the isotopes of that element. Two isotopes of sulfur are 32S
and 15.
________________
34S. An atom of the sulfur-32 isotope contains
15 protons and 16. ________________
16 neutrons. The sulfur-34 isotope
has 17 protons and 18
17. ________________
neutrons.
18. ________________
Each of the three known
isotopes of hydrogen has 19 proton(s)
19. ________________
in the nucleus. The most common hydrogen isotope has
20 20. ________________
neutrons. It has a mass number of 21 and
is called hydrogen-1. 21.
________________
Part 2 - Solve the
following problems.
22. Calculate the average atomic mass of oxygen given the percent abundance of
each of its naturally-
occurring isotopes: oxygen-16
is 99.76%, oxygen-17 is 0.037%, and oxygen-18 is 0.204%.
23. What is the mass of
6.00 moles of aluminum?
24. How many moles contain
8.53 x 1023 atoms of platinum?
25. How many atoms of
carbon are in 3.25 moles of carbon?
26. How many moles of SO2
are in 160.0 grams of SO2?
27. What is the mass of
3.58 x 1024 atoms of nitrogen?
28. How many molecules
does 80.0 grams of K2O contain?
Part 3 - Fill in the
following chart.
|
Name |
# of e- |
Atomic # |
Mass # |
# of no |
# of p+ |
Symbol |
|
arsenic
- 76 |
|
|
|
|
|
|
|
|
|
27 |
58 |
|
|
|
|
|
|
|
|
48 |
36 |
|
|
|
|
|
|
|
|
11B |
|
|
25 |
|
56 |
|
|
|
|
|
|
|
|
8 |
6 |
|
|
|
|
7 |
|
7 |
|
|
Answers to # 23 - 28:
23.) 162 grams 24.)
1.42 moles 25.)
1.96 x 1024
atoms 26.) 2.500
moles
27.) 83.2
grams 28.) 5.13 x 1023
molecules