CHEMISTRY CHAPTER THREE
You performed paper chromatography on some marker ink and found that one of the pigments had a retention factor of 0.25. The total distance the solvent traveled was 8.0 cm. How far did the pigment travel?
2.0 cm
The ability of iron to react oxygen is an example of
a chemical property
Pure substances are further divided into elements and compounds. Which best describes the rust found on a vehicle over time?
a compound
Which of the following is the most heterogeneous mixture?
a pizza
Which of the following is an example of a chemical change?
burning a candle
Which of the following changes to sugar is an example of a physical change?
dissolving it in coffee
Define cell path length.
distance light travels through the substance
Alcohol and water are best separated from one another by:
distillation
Which is a slow way to separate solid sugar from a solution of sugar water?
evaporation
Both gases and liquids:
have an indefinite shape
What is molar absorptivity?
how strongly light is absorbed by a particular substance through a set cell path
What type of property is density?
intensive
Which of the following is a chemical property of the element hydrogen?
it combusts in the presence of oxygen
If you decreased the cell path length, how will the absorption of light change?
it decreases
What happens when incident light hits a liquid?
it is reflected, transmitted and absorbed
Which of the following is not in the Beer's Law equation?
light wavelength
Which of the following is an extensive property?
mass
Which of the following is a physical change?
melting ice
_____ properties of matter can be determined without changing composition, while _____ properties of matter must change the composition of matter.
physical; chemical
What is the definition of intensive property?
properties that do not change with amount of matter
Homogeneous mixtures are also called
solutions
Which of the following is not an extensive property?
temperature
What does it mean that matter is conserved in physical and chemical changes?
the amount of matter stays the same
Ocean water is a good example of a mixture because
the mixture of water and salt can be physically separated
Why are intensive properties used to characterize matter?
they do not change with the amount of matter
