Chemistry Ch 3

If iron filings are placed with excess powdered sulfur in a beaker, the iron filings are still attracted by a magnet and could be separated from the sulfur with the magnet. Would this combination of iron and sulfur represent a mixture or a pure substance?

mixture

Consider three 80 g samples of water: one as ice, one as liquid, and one as vapor. How is this difference in volume related to the physical state involved?

Although the 80 g sample of water vapor contains the same amount of water as the solid and liquid sample (the same number of water molecules), there is a great deal of empty space in the gaseous sample.

Solutions containing nickel(II) ion are usually bright green in color. When potassium hydroxide is added to such a nickel(II) solution, a pale-green fluffy solid forms and settles out of the solution. The fact that a reaction takes place when potassium hydroxide is added to a solution of nickel(II) ions is an example of a _____ property.

Chemical

If powdered elemental barium and powdered elemental sulfur are poured into a metal beaker and then heated strongly, a very vigorous chemical reaction takes place, and the _____ barium sulfide is formed.

Compound

heterogeneous or homogeneous: Italian Salad Dressing

Heterogeneous

heterogeneous or homogeneous: clay.

Heterogeneous

heterogeneous or homogeneous: sand at the seaside.

Heterogeneous

heterogeneous or homogeneous: the wood from which the desk you are studying on is made.

Heterogeneous

heterogeneous or homogeneous: vinegar.

Homogeneous

What are the two characteristic properties of matter?

It occupies space, it has mass.

Magnesium metal is very malleable, and is able to be pounded and stretched into long, thin, narrow "ribbons" that are often used in the introductory chemistry lab as a source of the metal. If a strip of magnesium ribbon is ignited in a Bunsen burner flame, the magnesium burns brightly and produces a quantity of white magnesium oxide powder.

Magnesium burns in air.

The fact that solutions of nickel(II) nitrate are green colored is an example of a _____ property.

Physical

Elemental mercury is a dense, silver, odorless liquid. Are these characteristics of elemental mercury physical or chemical properties?

Physical Properties

Which two of the three states of matter are not very compressible?

Solid and Liquid

The processes of melting and evaporation involve changes in the _____ of a substance.

State

Consider three 80 g samples of water: one as ice, one as liquid, and one as vapor. How do the volumes of these three samples compare with one another?

The gaseous 80 g sample of water has a much larger volume than either the solid or liquid samples.

Although some elements are found in an isolated state, most elements are found combined as _____ with other elements.

compounds