Chapter 4 Practice                                                Name_______________________________

Period_____________ Date _____________

 Symbol Name Atomic Number Mass Number Number  of protons Number of neutrons Number of electrons Cobalt-58 28 58 33 40 Rhodium-103 78 117 118 50 84 60 1

1. An atom has 11 protons 11electrons and 10 neutrons. What is its

a. atomic number

b. mass number

c.  Name

d. charge

e.  Complete symbol

2. For argon-39, what is its

a.    Number of protons

b. Number of neutron

c.     Number of electrons

d.    Mass number

e.  atomic number

f.  Complete symbol

3. For  what is the

a.    Number of protons

b.    Number of neutron

c.     Number of electrons

d.    Mass number

e.  atomic number

f.  Name

5. For cobalt-60, what is its

a.    Number of protons

b. Number of neutron

c.     Number of electrons

d.    Mass number

e.  atomic number

f.  Complete symbol

6. For  what is the

a.    Number of protons

b.    Number of neutron

c.     Number of electrons

d.    Mass number

e.  atomic number

f.  Name

1. What is average atomic mass of Lithium if 7.42% exists as 6Li (6.015 amu) and 92.58% exists as 7Li (7.016 amu)?

2. Calculate the average atomic mass of Chlorine if you know that 75.77% exists as Chlorine-35 (34.969 amu) and 24.23% exists as Chlorine-37 (36.966 amu).

3. Rubidium is a soft, silvery-white metal that has two common isotopes, 85Rb and 87Rb. If the abundance of 85Rb is 72.2% and the abundance of 87Rb is 27.8%, what is the average atomic mass of rubidium?

4. Use the following information to determine thaverage atomic mass of  Neon

 Isotope Percent Abundance (%) Mass (a.m.u.) 20Ne 90.92 19.992 21Ne 0.26 20.994 22Ne 8.82 21.991

4. Titanium has five common isotopes. Use the information below to average atomic mass of titanium?

 Isotope Percent Abundance (%) Mass (a.m.u.) 46Ti 7.93 45.9526 47Ti 7.28 46.9518 48Ti 73.94 47.9480 49Ti 5.51 48.9479 50Ti 5.34 49.9448

6. Without doing any math, are there more Bromine-79 atoms or more Bromine-80 atoms on earth? Explain your reasoning. (Hint: look at the periodic table.)