Test Review – Matter and Change. Please Review your fill-in-blank notes and text Chapter 1.
1. Labs
a. Bunsen Burner Lab
i. Methane plus oxygen yields carbon dioxide and water (complete combustion.)
ii. Methane plus oxygen yields carbon monoxide and water (incomplete
combustion.)
iii. Safety concerns for B. burner use: tie back hair, never leave unattended etc.
b. Magnesium/Hydrochloric acid lab
i. Copper sulfate (blue crystals) dissolved in water. Dissolving is a physical change.
ii. Magnesium burns in air to produce magnesium oxide and magnesium nitride.
This is a chemical change because new substances were produced.
iii. Magnesium metal reacts with hydrochloric acid yield hydrogen gas and
magnesium chloride. (Chemical change.)
iv. Hydrogen gas burns in air to produce water (glowing splint.) Burning is a
chemical change known as “combustion.”
c. Dry Ice/Iodine Lab
i. What changes did you observe? Physical or chemical?
d. “What’s the Matter?” – Venn diagram activity
i. Atom, element, monatomic ion, polyatomic ion, molecule, compound- know
examples and definitions.
2. Ions and compounds- Please see your table of ions and study. Here are a few examples.
a. Positive 1- for example, Na1+ forms ionic compounds such as NaCl, sodium chloride
b. Positive 2 - Mg2+ forms compounds such as MgO, magnesium oxide
c. Positive 3 – Al3+ forms Al2O3, aluminum oxide
d. Remember to:
i. Use Roman numerals for transition metals (center of periodic table), like Iron
(III) means Fe3+
ii. Ionic compounds are neutral, i.e. they have a net, overall charge of zero.
iii. Groups 1A, IIA, IIIA always have a charge equal to their group number.
iv. Groups are vertical columns, periods are rows on the periodic table.
v. What are some properties of metals?
3. Changes
a. Physical changes- changes in state, like freezing, melting, etc. Dissolving, changing
shape as in bending, stretching, etc.
b. Be sure to know the names of the six possible changes of state and the phase change
they represent. For example, when a substance changes from a solid to a gas, it is
sublimation.
c. Chemical changes- result in the formation of a new substance. Burning, reacting,
oxidizing, etc. are key words that indicate. Look for gas bubbles, formation of a
precipitate (new solid), temperature changes, etc.
4. Properties
a. Physical- can be measured without changing the substance.
i. Intensive- examples: density, melting point, freezing point, boiling point,
conductivity, etc. There are too many of these to list here. Intensive properties
do not depend on the size of the sample.
ii. Extensive- properties defining the size of a sample. Mass, volume, length, etc.
b. Chemical- require the sample to change, by testing whether it reacts or not
i. Examples: corrosive, flammable, inert, oxidizing, etc.