Name: _________________________
Date: _____________________
Review: Atoms
1. The 3 particles of the atom are:
a. ______________________
b. ______________________
c. ______________________
b. ______________________
c. ______________________
2. Their respective charges are:
a. ______________________
3. The number of protons in one atom of an element determines the atom’s ______________________, and
the number of electrons determines its ______________________.
4. The atomic number tells you the number of ______________________ in one atom of an element. It also
tells you the number of ______________________ in a neutral atom of that element. The atomic number
gives the “_____________ “of an element as well as its location on the Periodic Table. No two different
elements will have the ______________________ atomic number.
5. The ______________________ of an element is the average mass of an element’s naturally occurring
atoms, or isotopes, taking into account the ______________________ of each isotope.
6. The ______________________ of an element is the total number of protons and neutrons in the
______________________ of the atom.
7. The mass number is used to calculate the number of ______________________ in one atom of an element.
In order to calculate the number of neutrons you must subtract the ______________________ from the
______________________.
8. Give the symbol and number of protons in one atom of:
Lithium __________________
Bromine __________________
Iron __________________
Copper __________________
Oxygen __________________
Mercury __________________
Krypton __________________ Helium __________________
9. Give the symbol and number of electrons in a neutral atom of:
Uranium __________________
Chlorine __________________
Boron __________________
Iodine __________________
Antimony __________________
Xenon __________________
10. Give the symbol and number of neutrons in one atom of:
(To get “mass number”, you must round the “atomic mass” to the nearest whole number)
Barium __________________
Bismuth __________________
Carbon __________________
Hydrogen ________________
Fluorine __________________
Magnesium ______________
Europium ________________
Mercury __________________
11. Name the element which has the following numbers of particles:
a. 26 electrons, 29 neutrons, 26 protons _____________________
b. 53 protons, 74 neutrons _____________________
c. 2 electrons (neutral atoms) _____________________
d. 20 protons _____________________
e. 0 neutrons _____________________
12. At a minimum, what information must you have to determine the identity of an element? ______________
A
A typical isotopic symbol takes this form: Z X
Where: X = element symbol; A = mass number [# of protons (p) + # neutrons (n)];
Z = atomic number [# of protons]; N = # of neutrons; A – Z = N
13.
14. In a neutral atom, # Protons = # Electrons: True or False?
15. Thallium (Tl) has two isotopes: thallium-203 and thallium-205. Thallium's atomic number is 81, and its
atomic mass is 204.38 amu. Which statement about the thallium isotopes is true?
a. There is more Tl-203 in nature
c. Tl-205 atoms have fewer neutrons
b. Atoms of both isotopes have 81 protons
d. The mass of the most common Tl atom = 204.38 amu.
16. Atoms consist of: (circle all that apply)
Protons
Neutrons
Molecules
Electrons
17. Which of these descriptions is incorrect?
Proton: positive charge, in nucleus, mass of = 1 amu
Electron: negative charge, mass of = 0 amu, in nucleus
Neutron: mass of = 1 amu, no charge
18. The atom that has atomic mass of 12 has ________________ protons.
1
2
3
4
5
6
12
8
19. What do you call an atom that is positively or negatively charged because it gained or lost one or more
electrons? ______
20. The valence electron(s) is/are the outermost electron(s) in an atom.
21. The center of an atom is called the: _______________
22. In an atom, the ______________ form a cloud around the nucleus.
23. Objects that are electrically neutral, become_____________ charged when they gain electrons.
24. In an element with a neutral charge, the atomic number is equal to the number of _________________
25. _____________ are particles with no charge.
Protons
Neutrons
Electrons
26. _____________ are negatively charged particles.
Protons
Neutrons
Electrons
27. _____________ are positively charged particles.
Protons
Neutrons
Electrons
28. The atom has the following parts ____________________________________
29. What charge do protons carry? ____________
30. Is an atom the smallest particle of matter? True False
31. Determine the average atomic mass of this mixture of naturally occurring isotopes of Barium.
Isotope
N.A.%
amu
Ba - 130
0.106%
_____________________
Ba - 132
0.101%
_____________________
Ba - 134
2.417%
_____________________
Ba - 135
6.592%
_____________________
Ba - 136
7.854%
_____________________
Ba - 137
11.23%
_____________________
Ba - 138
71.7%
Sum =
32. Some possible sources of experimental error are:
Inaccurate measurements; flawed methodology; poor experimental design; careless practices; inadequate or
inferior tools; unforeseen circumstances or occurrences