2.2. Classification of Matter http://www.ck12.org
Lesson Review Questions
Reviewing Concepts
- Why can’t a mixture be classified as a pure substance?
- Classify each of the following as a homogeneous or heterogeneous mixture.
a. salad
b. iced tea
c. soil
d. cooking oil
- When is filtration used to separate a mixture? When is distillation used?
- What is wrong with the following explanation of an experiment? “When it was heated, the sample of carbon
decomposed.” - Identify the following as either a chemical symbol or a chemical formula.
a. CO
b. Co
c. W
d. Be
e. HI
Problems
- Describe a way to separate a mixture of fine sand and table salt without having to directly sort tiny crystals
using tweezers. - Name the elements found in each of the following compounds.
a. ammonia (NH 3 )
b. saltpeter (KNO 3 )
c. glucose (C 6 H 12 O 6 )
d. millerite (NiS) - Identify each of the following items as an element, compound, or mixture. If it is a mixture, further classify it
as homogeneous or heterogeneous.
a. gasoline
b. calcium
c. carbon dioxide
d. blood
Further Reading / Supplemental Links
- Another method for separating a mixture is chromatography. You can see how bomb specialists use chro-
matography to identify the chemical components that were used in the making of the bomb. There is also a
chromatography activity that you can do at home! Go to http://www.pbs.org/wgbh/nova/bombingactivity/chroma
tog.html.