Comments

Matter Specific Properties (continued)


Malleability

Property that allows matter to be shaped. There are malleable and non-malleable materials.

Property that allows you to turn materials into wires. An example is copper, which is used in the form of wires in electrical installations and iron in wire manufacturing.

Some substances have the property of being attracted by magnets, they are magnetic substances.

It is also called specific mass of a substance is the ratio (d) between the mass of that substance and the volume occupied by it.

With a scale we can determine the mass of cork pieces of known volume. Thus, for example, it is experimentally determined that (for the variety of cork used):

  • 1 cm3 of cork has mass 0.32 g;
  • 2 cm3 of cork have mass 0.64 g;
  • 100 cm3 of cork have mass 32 g;
  • 1,000 cm3 of cork have mass 320 g.

Similarly, the mass of lead pieces of known volume can be determined. For example, we get:

  • 1 cm3 lead has a mass 11.3 g;
  • 2 cm3of lead have mass 22,6 g;
  • 100 cm3 of lead have mass 1,130 g;
  • 1,000 cm3 of lead have mass 11,300 g.

Did you notice any regularity?

The mass and volume of cork are directly proportional. When the volume increases, the mass increases in the same proportion. Mathematically, we can say that the ratio (division) between the mass and volume of a piece of cork gives constant result. The same can be said for lead.

The concept of density

The mass to volume ratio for cork is:

The result obtained (0.32g / cm3) is the density of cork, a quantity that tells us how much mass there is in a certain volume. 1cm volume3 of cork has mass 0.32 g, a volume of 2 cm3 It has mass of 0.64g and so on.

For lead we have:

The density of lead (11.3 g / cm3) is therefore different from the density of cork. One cubic centimeter of lead has a greater mass than one cubic centimeter of cork.

Let's define more generally.

In words: The density of an object or a sample of a certain material or substance is the result of dividing its mass by its volume.
In equation:

The unit of density is composed of a unit of mass divided by a unit of volume. So we can express it, for example, in g / cm3, g / L, kg / L etc.