1)Compare the properties of metals nonmetals and metolliods?

2)Why can elements and compound be considered pure substance?

3)What is the difference between colloids and suspension?

1) To compare the properties of metals, nonmetals, and metalloids, we can use the periodic table. The periodic table is organized in a way that separates these three groups based on their characteristics.

- Metals: Most elements on the left side of the periodic table are metals. They have shiny luster, are good conductors of heat and electricity, and are malleable (can be hammered into thin sheets) and ductile (can be drawn into wires). Metals tend to lose electrons and form positive ions.
- Nonmetals: Most elements on the right side of the periodic table are nonmetals. They have dull luster, are poor conductors of heat and electricity, and are brittle (break easily). Nonmetals tend to gain electrons and form negative ions.
- Metalloids: Metalloids are found along the "staircase" line on the periodic table, between metals and nonmetals. They exhibit properties of both metals and nonmetals, having some metallic and nonmetallic characteristics. Metalloids can conduct electricity under certain conditions and can be either brittle or malleable.

By referring to the periodic table, you can easily identify and compare the properties of metals, nonmetals, and metalloids.

2) Elements and compounds can be considered pure substances because they have a specific chemical composition and consistent properties throughout a given sample.

- Elements: Elements are substances made up of only one type of atom. Each element is uniquely defined by its atomic number, which represents the number of protons in its nucleus. For example, pure gold (symbol: Au) consists solely of gold atoms, and pure oxygen (symbol: O) consists solely of oxygen atoms. Elements cannot be broken down into simpler substances through ordinary chemical means.
- Compounds: Compounds are substances made up of two or more different elements chemically bonded together in a fixed ratio. For example, water (chemical formula: H2O) is a compound consisting of two hydrogen atoms and one oxygen atom. Compounds can be broken down into their constituent elements through chemical reactions.

Both elements and compounds have characteristic physical and chemical properties that remain consistent throughout a given sample. They do not exhibit variations in composition or properties like mixtures do. Therefore, elements and compounds are considered pure substances.

3) Colloids and suspensions are both types of heterogeneous mixtures, but they differ in terms of the size of the particles dispersed in the surrounding medium.

- Colloids: Colloids are mixtures in which particles (called colloidal particles) are dispersed evenly throughout a medium (such as a liquid, solid, or gas). The size of the colloidal particles falls between 1 nanometer and 1000 nanometers. Examples of colloids include milk, fog, and gelatin. Colloidal particles are small enough to remain suspended in the medium without settling or dissolving. They scatter light, leading to the Tyndall effect (visible beam of light passing through the mixture).
- Suspensions: Suspensions are mixtures in which larger particles are dispersed in a medium. These particles are usually larger than 1000 nanometers. A suspension is not homogeneous and will eventually settle due to gravity, forming layers. Examples of suspensions include muddy water and orange juice with pulp.

In summary, colloids contain smaller particles that remain suspended and exhibit the Tyndall effect, while suspensions contain larger particles that tend to settle.