Introduction to Chemistry Chapter 1 Lesson 2 Classifying Matter Introduction to Chemistry Chapter 1 Lesson 2

Smaller Than Small What’s the smallest thing you can think of? A grain of sand? A speck of dust? If you look at these items under a powerful microscope, you’ll see that they’re made up of smaller and smaller pieces. All matter is made up of very tiny particles called atoms. Atoms are so small, there is a special unit of measure used to describe them called a nanometer (nm). A nanometer is equal to 1/1,000,000,000 or one-billionth of a meter!

What Is Matter Made Of? Scientists know that all matter in the universe is made of more than 100 different substances, called elements. An element is a substance that cannot be broken down into any other substances by chemical or physical means. Elements are the simplest substances. Each element has specific physical and chemical properties, which can be used to identify it. Elements are represented by one- or two- letter chemical symbols.

What Is Matter Made Of? According to the particle theory, all matter is made up of atoms. An atom is the basic particle from which all elements are made. An atom has a positively charged center, or nucleus, surrounded by a negatively charged “cloud.  Atoms of most elements can combine with other atoms by forming chemical bonds.    A chemical bond is a force of attraction between two atoms. The result of a chemical bond is often a molecule, or a group of two or more atoms held together by chemical bonds. A molecule can be made of atoms of different elements or atoms of the same element.

What Is Matter Made Of? A compound is another type of substance. A compound is made of two or more elements that are chemically combined in a set ratio. A compound is represented by a chemical formula, which shows the elements in the compound and the combining ratios of their atoms. When elements combine chemically, they form compounds with properties different from those of the elements.

What Are Two Types of Mixtures? Elements and compounds are substances, but most materials are mixtures. A mixture is made of two or more substances that are together in the same place but whose atoms are not chemically combined. Each substance in a mixture keeps its own properties and is not combined in a fixed ratio.

What Are Two Types of Mixtures? A mixture can be heterogeneous or homogeneous. In a heterogeneous mixture, the different parts can usually be seen and easily separated. The substances in a homogeneous mixture are so evenly mixed that they cannot be seen and are difficult to separate. A solution is a homogeneous mixture. Methods used to separate mixtures include filtration, distillation, evaporation, and magnetic attraction.

What Makes Up Matter? https://www.pearsonrealize.com/community/program/ b5aea82b-ad2c-3447-b122- 4b953e6a7cba/17/tier/093fbf6d-063c-353c-8057- f7001e301701/18/lesson/4a97331c-8e9c-31bc-a7fa- 29949895c1db/18/content/f9160225-c88b-3f81-b556- e11876c09c1b/19

Classifying Matter Common Objects in Nanometers (nm)

Classifying Matter Atoms and Molecules Molecules are made up of groups of atoms. How many atoms are in each of these molecules?

Classifying Matter Compounds From Elements What are the properties of copper, sulfur, and copper sulfide?

Classifying Matter Mixtures Which of these foods are heterogeneous and which are homogeneous?

Classifying Matter Separating Mixtures Which type of separation method is used in each of these situations?