​Materials have physical properties that we can directly observe.

​

But this doesn't tell you everything you need to know about a material. Materials also have chemical properties.

​

​

Chemical Properties

Properties that can ONLY be observed when one substance changes into a different substance are called CHEMICAL PROPERTIES.

​

​

​Chemical Properties

For example, when you leave an iron nail outside, it will eventually rust. The iron reacted with oxygen to form iron oxide (rust).

​

The iron oxide or RUST, is a NEW SUBSTANCE!​​

​

A new substance must form for it be a chemical change​.

​Chemical Properties vs Physical Properties

​Physical properties are easy to observe by looking at, touching or smelling. By physically interacting with them.

​

Chemical properties can only be determined after a chemical change (or a chemical reaction) occurs.​

​Chemical Properties

​Examples of Chemical Properties are reactivity, flammability, acidity.

​Reactivity is the ability for a substance to form a chemical reaction with another substance.

Flammability is the ability for a material or substance to be ignited.

​When you burn something, it changes into something else. ​

​If you burn paper, a chemical reaction occurs to create a new substance: smoke and ash.

​Acidity is determined by the pH of a substance. If something has a low pH, it is acidic.

​

If the pH is high, it's basic.

​Not all acids burn through objects. You interact with acids everyday.

Chemical Changes

A CHEMICAL CHANGE is when a substance changes from one substance into another. This is a also called a chemical reaction. One chemical reacts with another chemical.

​

The rust will not turn back into iron. Chemical changes are irreversible.

​Chemical vs. Physical Quiz!

​When choosing the materials that make up your product, you will need to understand their chemical properties as well. ​

You wouldn't want to make A fireFighter's vest out of material that's flammable. ​

​acidity can help with preserving food, and determine how sour a food can be.

​Earlier this year, at a hotel, two cleaning agents were apparently mixed together in the basement of the building. The reaction between the two chemicals generating vapors that filled up part of the resort. 23 people died in this accident.

​UNDERSTANDING THE REACTIVITY OF MATERIALS IN A PRODUCT CAN BE THE DIFFERENCE BETWEEN LIFE AND DEATH.