Question

teks 8.6.a
models of matter
8.6.a: explain by modeling how matter is classified as elements, compounds, homogeneous mixtures, or heterogeneous mixtures;
matter is anything that has mass and takes up space. there are three major classes of matter: elements, compounds, and mixtures. an atom, the smallest unit of an element that maintains the properties of that element, is the basic building block for all three types of matter. atoms are combined in different ways to produce different elements, compounds, and mixtures.
elements are made up of one or more of the same kind of atom chemically combined. they are pure substances that have definite physical and chemical properties. regardless of the amount of a pure substance present, it will always have the same properties because it is made up of one type of particle.
elements are classified based on differences in their physical and chemical properties. broadly speaking, elements are classified as metals, nonmetals, or metalloids.

• metals are generally shiny, conduct heat and electricity well, and can be shaped into thin sheets and wires.
• nonmetals are not shiny and do not conduct heat or electricity well.
• metalloids have some properties of both metals and nonmetals.

the periodic table of elements is a tool used to arrange the over 100 known elements into groups that have similar properties.
how could molecules of compounds in a model of a homogeneous mixture be changed to represent a heterogeneous mixture?

• separate the molecules into individual atoms, and spread out the atoms.
• move the molecules around so that all of the compounds are mixed evenly throughout.
• separate all the molecules, move them around, and attach them with different molecules.
• move the molecules around so that one compound is clustered together, and the other compound is clustered together with only a little mixing.

Explanation:

To determine the correct answer, we analyze the definitions of homogeneous and heterogeneous mixtures. A homogeneous mixture has a uniform composition (molecules evenly mixed), while a heterogeneous mixture has a non - uniform composition (molecules of different compounds clustered separately with little mixing).

• Option 1: Separating into atoms and spreading them out does not relate to the difference between homogeneous and heterogeneous mixtures in terms of compound molecule distribution.
• Option 2: Moving molecules to be evenly mixed is characteristic of a homogeneous mixture, not a way to get a heterogeneous mixture.
• Option 3: Separating and attaching with different molecules is not the correct way to represent the difference between these two types of mixtures.
• Option 4: Moving molecules so that one compound is clustered and the other is clustered with little mixing matches the non - uniform composition of a heterogeneous mixture.

Answer:

D. Move the molecules around so that one compound is clustered together, and the other compound is clustered together with only a little mixing.