Chemical properties are properties that are determined by changing the identity of matter. Some examples for chemical properties are how the matter reacts to air, to water, to an acid, to a
base, to other chemicals, and to heat.
For example, flammability is the chemical
property of how easily something will
burn or ignite. Heat of combustion is a
chemical property that defines how much
energy (as heat) is released when
something is completely burned for
combusted).
When a sample of silicon, which is a major
part of computer chips, is exposed to air, it
oxidizes (rusts). This means it forms silicon
dioxide or silica on the surface of the
sample. In order to prevent uncontrolled
oxidation, the components of computer
chips already have controlled layers of
silicon dioxide or silica on them.
A common theme here is that a chemical property only becomes evident or can be measured during or after a chemical reaction. To measure or observe a chemical property the substance
undergoes a chemical reaction and actually changes identity. When your old iron rail rusts (oxidized, it actually changes from iron to iron oxide (runt. You no longer have the same
substance that you started with
Q26. Find out some of the chemical properties of aluminum and iron are and describe them
here./nSolubility, the amount of substance that will
dissolve in a solvent, is a physical property we will
discuss more in Lesson 10.
CC
Viscosity, the measure of a fluid's resistance to flow is a
physical property. Liquids with low viscosity pour
faster than those with higher viscosity
Conductivity, the ability of a solid to act as an electrical conductor or an electrical insulator, is a physical property
Substances (such as metals) that readily conduct electricity are called electrical conductors
Substances (such as most non-metals) that do not allow electric current to flow are called insulators
Density, is a physical property, but we will discuss it next
Q27. Describe physical properties of aluminum and iron./nQ28. Imagine you want to create an art and craft project to be displayed in your garden. If
you have a choice to use either aluminum or iron for this project, which material would you
choose? Please, use the properties that you found for answers Q1 and Q2 to explain your
reasoning
Q29. List and define at least four more physical properties not mentioned above.
Density
Density in the oftence per unit kame. It is a derived unit. These are units that
You do not neure density directly, it is calculated after measuring the mass and volume of something Density does change whe
Ap
Dersity Ma
ab
Since the Sibase units for mass are klograme, and the infor
Another common way of expressing density is a percubic center
which is often abbreviated one of these two ways (1 cubic centimeter-1
ter
Solubility and intermpletuar forces (Chemi
Solubility
tempt Solublchy
Whcademy
Q30. Assuming all measurements are under normal conditions (referred to as STP
or Standard Temperature and Pressure). Search and find the following information
(again you may find the Dynamic Periodic Table helpful).
• What is the density of 100.0 grams of sodium? What is the density of 128 kg
of sodium?
• What is the density of 100.0 grams of silver? What is the density of 128 kg of
silver?
• What does this tell you about the correlation of density to the quantity you
have of a substance?
Fig: 1
Fig: 2
Fig: 3