Study Guide – Unit 1 Periodic Table ANSWERS
Structure of an atom
1. List the three subatomic particles which make up an atom. Include their location, charge, and
atomic mass.
a. Electron
Negative charge
Electron Cloud
b. Proton
Positive charge
Nucleus
c. Neutron
Neutral charge
Nucleus
2. In a neutral atom, which two subatomic particles are equal in number to each other?
Protons and Electrons
3. What does the atomic number of an element indicate?
The number of protons in the atom of that element
4. What is an isotope?
Atoms with the same number of protons, but different masses due to a different
number of neutrons
5. Will two different atoms of carbon always have the same number of protons?
Yes
Element key
13
Al
26.982
Aluminum
1. What are the number of protons, neutrons, and electrons in an atom of aluminum?
a. Protons = 13
b. Neutrons = 14
c. Electrons = 13
Bohr Model
1. How do you know how many energy levels (orbits) a Bohr model will have?
a. By the period the element is located in
2. How many electrons can each energy level hold?
1st – 2
2nd – 8
3rd – 18
The Periodic Table
1. How is the periodic table arranged? Increasing atomic number
2. What are the vertical columns ↕ called? Groups or Families
3. What are the horizontal rows ↔ called? Periods
4. Why are elements put into groups? Same number of valence electrons
5. What is a valence electron? Number of electrons on the outer energy level (shell)
6. Know how many valence electrons each group has
7. Which group of metals are highly reactive and why? Alkali Metals. Only 1 ve- to lose
8. Which group of non-metals are highly reactive and why? Halogens. Only 1 ve- to gain
9. Name some physical properties of metals: luster, ductile, malleable, conductor of heat and
electricity
10. Name some physical properties of non metals: no luster, brittle, not a good conductor
11. What are metalloids and where are they found on the periodic table? Share properties of metals
and metalloids. On zig-zag line starting at Boron.
12. Which type of element is the most abundant – metals, non metals, or metalloids? Metals
13. Using a periodic table, write the name of the group the following are located in:
Element
Group’s name
Element
Group’s name
Mg
Alkaline-Earth Metal
Li
Alkali-Metal
Al
Boron
Si
Carbon
Ne
Noble Gas
Cl
Halogen
14. Why are the elements in group 18 called Noble gases (inert gases)? They are non-reactive.
Unit 1 Chemical formulas, compounds, reactions and bonds
1. What is a compound? Two or more atoms from different elements in a chemical bond
2. What are the three parts of a chemical formula? Coefficient, subscript and symbol
3. Label the parts of the following chemical formula:
4 H2O
4 → Coeffiecient
2 → Subscript H and O → Symbols
4. What do subscripts indicate? # of atoms What do coefficients indicate? # of molecules
5. How many atoms of each element are present in the following compounds:
4 H2O
8H 4O
CO2
1C 2O
3 NH3
3N 9H
6. What are atoms with a positive or negative charge called? Ions
7. If an atom has a negative charge, what particles does it have more of, protons or electrons?
electrons
8. What does an element’s oxidation number indicate? Number of e- the atom will give or take in a
chemical reaction
9. Using the periodic table, write the oxidation number for the following elements?
Mg2+ O2ClS2N310. Draw an electron dot diagram for the following elements: Mg, S, N, Li, Ne
11. What is the name of the bond that occurs when atoms give or take electrons? Ionic bond
12. What is the name of the bond that occurs when atoms share electrons?
13. Ionic bonds take place between what two types of elements? Metal and non-metal
14. What is the name of an ion that has a negative charge? anion Positive charge? cation
15. Name the following compounds:
MgCl2 – Magnesium Chloride
BeBr2 – Beryllium Bromide
Li2S – Lithium Sulfide
Mg3N2 – Magnesium Nitride
16. In the formula aluminum sulfide, which of the two elements present is the cation? Aluminum
because it is the positive ion
17. Label the following as either covalent or ionic bonds:
18. Complete the following ionic bond table:
Elements
Oxidation #
Formula
Name
3+
Al + F
Al F
AlF3
Aluminum Flouride
Li + O
Li+ O2Li2O
Lithium Oxide
Ca + Br
Ca2+ BrCaBr2
Calcium Bromide
Mg + N
Mg2+ N3Mg3N2
Magnesium Nitride
19. What is the difference between an endothermic and exothermic reaction?
Endothermic absorbs heat (reaction gets cold)
Exothermic releases heat (reaction gets hot)
20. What is a catalyst? A substance that accelerates or causes a reaction without itself being
changed by the reaction.