Lesson 2
Home Up Safety Precautions Lab Techniques Observing Chemical Reactions Chemical Reactions Creating Materials in New Phases Chemical Reactions Creating Materials with New Colors Chemical Reactions Creating or Using Heat Energy Describing Chemical Reactions Distinction Between Chemical and Physical Changes Quick Quiz on Chemical Reactions

 

Quick Quiz on Chemical Reactions

Determine whether each of the following observations indicates a chemical reaction. Check your answers below.

1.  "A homogeneous, transparent, yellow liquid is mixed with a homogeneous, transparent, colorless liquid and a homogeneous opaque yellow solid is formed that settles to the bottom of the container with a homogeneous, transparent, pale yellow liquid remaining above it."

2.  "A homogeneous, opaque, red solid is placed in sunlight and after a period of time it becomes a homogeneous, opaque, orange solid."

3.  "A homogeneous, colorless, transparent solid at -5oC is placed in sunlight and after a period of time becomes a homogeneous colorless transparent liquid at +5oC."

 

Answers to Quick Quiz on Chemical Reactions

1.  "A homogeneous, transparent, yellow liquid is mixed with a homogeneous, transparent, colorless liquid and a homogeneous opaque yellow solid is formed that settles to the bottom of the container with a homogeneous, transparent, pale yellow liquid remaining above it." Chemical reaction.

2.  "A homogeneous, opaque, red solid is placed in sunlight and after a period of time it becomes a homogeneous, opaque, orange solid." Chemical reaction.

3.  "A homogeneous, colorless, transparent solid at -5oC is placed in sunlight an after a period of time becomes a homogeneous colorless transparent liquid at +5oC." Physical change, not a chemical reaction.