1. Determine whether each of the following represents a physical property or a chemical property.
Vinegar has a pungent odor.
Carbon cannot be decomposed.
Sulfur is a bright yellow.
Sodium chloride is a crystalline solid.
Water does not burn.
Ten mL of mercury is a liquid at 25°C.
Oxygen is not combustible.
Aluminum combines with oxygen to form a protective oxide coating.
The density of water at 4°C is g/mL.
Hydrogen gas is very flammable.
U4-4

2. Determine whether each of the following represents a physical property or a chemical property.
Physical (intensive)
Chemical
Physical (extensive - 10 mL; intensive liquid at 25°C)
U4-4

3. State whether each of the following represents a chemical change or merely a physical change.
The lasagna was baked in the oven for 1 hour.
In the lab, a student mixes 2 mL of ammonium chloride with 2 mL of hydrochloric acid in a test tube. He notices that the test tube become cooler.
When potassium iodide and lead(II) nitrate are mixed together, a yellow solid forms.
A few grams of table salt are placed in a small beaker of deionized water; the salt crystals “disappear” and the liquid in the beaker remain clear and colorless.
A copper statue, over time, turns green.
In the lab, a student cuts magnesium ribbon into 1-cm strips.
25 grams of ice melted at room temperature.
U4-4

4. U4-4 Chemical (cooking always indicates chemical)
State whether each of the following represents a chemical change or merely a physical change.
Chemical (cooking always indicates chemical)
Chemical (indicator: change in energy)
Chemical (indicators: change in color and formation of precipitate)
Physical (forms mixture not a new substance)
Chemical (indicator: change in color)
Physical (changes size not composition)
Physical (phase changes are always physical)
U4-4