elements compounds and mixture - Sentence Scramble Worksheet ... - Free Printable

Worksheet: Elements, Compounds, and Mixtures Fill-in-the-Blanks

#### 1. Properties of Elements:
- A pure substance contains only one kind of atom.
- Without a nuclear reaction, an element cannot be broken down into simpler materials.
- There are over 100 existing elements listed and classified on the periodic table.

#### 2. Properties of Compounds:
- A pure substance contains two or more kinds of elements.
- The atoms are chemically combined in some way. Often, but not always, they come together to form groups of atoms called molecules.
- Compounds cannot be separated by physical means. It requires a chemical reaction.
- The properties of a compound are generally different than the properties of the elements in its makeup.

#### 3. Properties of Mixtures:
- A mixture consists of either two or more substances or elements NOT chemically combined.
- Mixtures can be uniform and known as homogeneous mixtures.
- Mixtures can also be non-uniform, known as heterogeneous mixtures.
- Mixtures can be separated by physical or mechanical methods.
- A mixture has properties similar to its components.

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Explanation of the Solution:

#### 1. Properties of Elements:
- Atom: An element is defined as a pure substance that consists of only one type of atom. For example, hydrogen (H) is an element made up of hydrogen atoms.
- Cannot: Elements cannot be broken down into simpler substances through chemical reactions; this requires nuclear reactions, such as fission or fusion.
- Periodic Table: The periodic table is a tabular arrangement of all known elements, organized based on their atomic number, electron configurations, and chemical properties.

#### 2. Properties of Compounds:
- Elements: A compound is a pure substance formed when two or more different elements combine chemically. For example, water (H₂O) is a compound made from hydrogen and oxygen.
- Chemically, Molecules: In compounds, atoms are bonded together chemically. These bonds can form molecules (e.g., H₂O), which are groups of atoms held together by chemical forces.
- Cannot, Chemical: Compounds cannot be separated into their constituent elements using physical methods like filtration or distillation. They require chemical reactions to break the bonds between atoms.
- Different: The properties of a compound are usually different from those of its constituent elements. For example, water (H₂O) is a liquid at room temperature, while hydrogen (H₂) and oxygen (O₂) are gases.

#### 3. Properties of Mixtures:
- Substances, Elements: A mixture is composed of two or more substances (which could be elements or compounds) that are physically combined but not chemically bonded. For example, saltwater is a mixture of sodium chloride (NaCl) and water (H₂O).
- Homogeneous Mixtures: Homogeneous mixtures have a uniform composition throughout. Examples include saltwater or air.
- Heterogeneous Mixtures: Heterogeneous mixtures have non-uniform compositions. Examples include sand and water or oil and water.
- Physical, Mechanical: Mixtures can often be separated using physical or mechanical methods, such as filtration, distillation, or centrifugation, because the components are not chemically bonded.
- Similar: Mixtures retain the properties of their components. For example, a mixture of iron filings and sulfur will have the magnetic property of iron and the yellow color of sulfur.

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Final Answer:

\[
\boxed{
\begin{array}{l}
\text{1. atom, cannot, periodic table} \\
\text{2. elements, chemically, molecules, cannot, chemical, different} \\
\text{3. substances, elements, homogeneous mixtures, heterogeneous mixtures, physical, mechanical, similar}
\end{array}
}
\]