Enriched Chemistry Study Guide: 2nd Semester Exam
The Periodic Table & Trends
Describe Mendeleev’s Periodic Table and how he organized it.
Why did Mendeleev leave blanks in his Periodic Table?
How is it that Mendeleev was able to accurately predict many of the properties of
Germanium and Gallium (yet to be discovered)?
Why did Moseley change the order of the elements from atomic mass to atomic
number? (And, why didn’t Mendeleev think of this?)
What is the Periodic Law?
Given that elements were grouped together by similar chemical properties, it was
later discovered that “what” gave these elements similar chemical properties?
The vast majority of elements are good conductors of electricity, shiny, and
malleable…as a broad class they are called what and where are they located?
Silicon is a semiconductor and is classified as a?
Many of the groups have been given specific names…for instance, why is group 18
called the Noble Gases?
Where are the halogens, alkali metals, and alkali earth metals found? What do you
know about these groups (reactivity, valence electrons, and properties)?
The “d” block of metals are called what?
What happens to the size of atoms as you go down a group or across a period?
What happens to the size of a metal atom when it forms its ion?
What happens to the size of a non-metal atom when it forms its ion?
What happens to the amount of ionization energy needed as you move across a
period on the periodic table? Why?
What happens to the amount of electronegativity as you move down a group? Why?
Ionic Bonding & Names of Compounds
How does the Periodic Table inform you of the valence electron count for elements
in the representative groups?
Be able to draw Lewis Dot Diagrams for all elements in the representative groups,
for example, draw Lewis Dot Diagrams for: K, Mg, Al, C, P, S, Br, Xe…
What is the Octet Rule?
All metals will lose electrons to non-metals, forming what?
When a non-metal gains electrons, it is called a?
Once a metal loses valence electrons and non-metals gain valence electrons, their
electron configurations look similar to what?
The charge assigned to an ion once it has lost or gained electrons is called?
The overall charge of an ionic compound is what?
The subscripts used in a chemical formula indicate what?
Another name for the chemical formula of an ionic compound is?
Be able to note some properties of ionic compounds…What state are they in at room
temperature? What happens to a solution when an ionic “salt” is dissolved into it?
How do their melting points compare to covalent compounds?
Be able to name simple, binary ionic compounds, such as NaCl, MgO, AlN, etc.
Given the name of a compound, be able to write a correct chemical formula…
Be able to name a compound that consists of metal ions that can have multiple
charges…like CuCl or CuCl2…
Must know that Ag and Zn never have multiple charges, and therefore never need a
roman numeral in the name…
Know the formulas and charge of 12 common polyatomic ions…
Be able to write formulas of compounds containing polyatomic ions…for example:
Ammonium Sulfate, Lead II Nitrate, Silver Phosphate, Potassium Carbonate, Sodium
Hydroxide.
What is the name of the following acids: HCl, H2SO4, HNO3, H2CO3, H3PO4?
What makes these compounds acids?
Covalent Compounds
What is a covalent bond?
How many covalent bonds can an oxygen atom form? A nitrogen atom? A carbon
atom?
Does a nitrogen molecule consist of single, double, or triple covalent bonds?
Why are elemental nitrogen, oxygen, hydrogen, chlorine, and fluorine always in the
diatomic state?
Draw the Lewis Dot diagrams of CO2, H2O, NH3, CH4, and C2H4
Given VSEPR Theory…what are the shapes of these molecules?
Why is it necessary to use prefixes in naming many of the covalent molecules?
What is the difference between dispersion forces and dipole-dipole interactions?
What type of molecules exhibit hydrogen bonding?
Metallic Compounds
Be able to describe metallic bonding as metallic cations surrounded by a sea of
mobile valence electrons.
What is an alloy?
Chemical Reactions
What is the difference between reactants and products? Where are they written in a
chemical equation?
What does the arrow () in a chemical equation mean?
What is the function of catalyst?
What do the italicized letters, s, l, g, and aq represent?
Why is it important to balance a chemical equation using coefficients and NOT
changing subscripts on chemical formulas?
What “law” are you applying when you balance a chemical equation?
Identify the types of chemical reactions below and balance the reactions:
Fe2O3

Na +
O2 
Mg +
CuCl2 
Fe +
O2
Na2O
O2 
_________________________________
MgCl2 +
NaOH + HClO3 
C3H8 +
_________________________________
Cu _________________________________
NaClO3 + H2O ___________________________________
CO2 +
H2O ____________________________
Be able to write complete, balanced equations given word equations of a chemical
process:
Silver nitrate reacts with Tin II Sulfate to yield Tin II nitrate and silver sulfate.
Iron II oxide reacts with oxygen gas to produce Iron III oxide.
Zinc phosphate reacts with Lead II nitrate to produce Lead II phosphate and zinc
nitrate.
What is a precipitate? Why does it form?
Given a series of single replacement reactions amongst metals and their cations, be
able to determine the activity series amongst the tested metals.
Stoichiometry
A balanced chemical equation can be interpreted in terms of different quantities,
including numbers of atoms, molecules, or moles; mass; and volume.
Coefficients are interpreted as the number of mole ratios that compounds relate to
each other in a given chemical reaction.
Remember, a chemical equation is balanced on both sides of the equation by particle
count (therefore mole count) and by mass.
Interpreting coefficients as number of moles, demonstrate how the following
chemical equation abides by the Law of Conservation of Mass:
N2 + 3 H2  2 NH3
Write mol/mol conversion factors relating nitrogen to hydrogen, nitrogen to
ammonia, and hydrogen to ammonia (6 in all).
Given 5 moles of nitrogen gas, how many moles of hydrogen are needed for a
complete reaction?
Given 10 moles of nitrogen gas, how many moles of ammonia will be produced given
excess hydrogen gas?
Given 14 grams of nitrogen gas, how many moles of hydrogen gas are needed?
Given 7 grams of nitrogen gas, how many grams of hydrogen gas are needed?
Given 112 grams of nitrogen gas, how many grams of ammonia will be produced?
Given 56 grams of nitrogen gas, what volume of ammonia will be produced? (at STP)
Given 14 grams of nitrogen gas and 4 grams of hydrogen gas, what mass of ammonia
will be produced? What is the limiting reagent? How many moles of the excess
reagent are left over?
Given 42 grams of nitrogen gas and 8 grams of hydrogen gas, what volume of
ammonia will be produced? What is the limiting reagent? How many grams of the
limiting reagent are left over?
15.0 grams of nitrogen reacts with 7.00 grams of hydrogen gas; 10.5 grams of
ammonia is the actual yield. What is the % yield of your experiment? (determine
limiting reagent first…)
Given 24.8 grams of calcium carbonate, you go about heating it to decompose it to
calcium oxide and carbon dioxide. Your actual yield is 10.5 g of carbon dioxide.
What is the % yield of your experiment?
What mass of sodium azide, NaN3, is needed to produce 6 Liters of nitrogen gas (at
STP)? Sodium azide undergoes “simple” decomposition in air bags…
Properties of Gases:
Know all components of the Kinetic Theory of Gases and how real gases deviate
from this…
Be able to convert from pressure units of atm to kPa to mmHg (also known as Torr).
Know who discovered the mathematical relationships of pressure, volume, moles,
and/or temperature of gases as well as being able to apply those relationships.
Be able to use the combined gas law when conditions on a gas change.
Know how the absolute temperature scale was derived (i.e. the Kelvin scale).
Be able to use the combined gas law and Dalton’s law of partial pressures to analyze
a gas produced in an experiment (over water).
Be able to use the ideal gas law and balanced chemical equations to predict volumes
or densities of gases produced during a chemical reaction.
Be able to apply Graham’s Law of Effusion in determining which gas molecule is
moving faster at a given temperature.
Acids & Bases:
Be able to recognize an acid or base as defined by Arrhenius or Bronsted & Lowry.
Be able to explain the difference between a strong or weak acid/base.
Be able to use the Kw of water to determine the concentration of an acid/base as
well as its pH/pOH.
Be able to use a base of a known concentration of a base to analyze an acid of an
unknown concentration.
Be able to distinguish between an equivalence point and an end point of a titration.
Be able to distinguish between titration curves of a strong acid/strong base vs. a
weak acid/strong base.