Science - 2017-18
PS.2 b, d-e - Elements, Compounds, & Properties
The student will investigate and understand the nature of matter. Key concepts include
b) elements, compounds, mixtures, acids, bases, and salts;
d) physical properties; and
e) chemical properties.
Bloom's Levels: Analyze; Understand
- Matter is classified by its chemical and physical properties.
- I can explain why certain substances react with one another and others don't.
- I can identify an unknown substance found on the kitchen counter.
UNDERSTANDING THE STANDARD
- Matter can be classified as elements, compounds, and mixtures. The atoms of any element are alike but are different from atoms of other elements. Compounds consist of two or more elements that are chemically combined in a fixed ratio. Mixtures also consist of two or more substances, but the substances are not chemically combined.
- Compounds can be classified in several ways, including:
- acids, bases, salts
- inorganic and organic copounds.
- Matter can be described by its physical properties, which include shape, density, solubility, odor, melting point, boiling point, and color. Some physical properties, such as density, boiling point, and solubility, are characteristic of a specific substance and do not depend on the size of the sample. Characteristic properties can be used to identify unknown substances.
- Equal volumes of different substances usually have different masses.
- Matter can also be described by its chemical properties, which include acidity, basicity, combustibility, and reactivity. A chemical property indicates whether a substance can undergo a chemical change.
In order to meet this standard, it is expected that students will
b) describe how to determine whether a substance is an element, compound, or mixture.
define compounds as inorganic or organic. (All organic compounds contain carbon.)
describe what a salt is and explain how salts form.
d) distinguish between physical properties (i.e., shape, density, solubility, odor, melting point, boiling point, and color) and chemical properties (i.e., acidity, basicity, combustibility, and reactivity).
find the mass and volume of substances and calculate and compare their densities.
e) analyze the pH of a solution and classify it as acidic, basic, or neutral.
determine the identity of an unknown substance by comparing its properties to those of known substances.
matter, particle theory of matter, element, compound, mixture, solvent, pH scale, base, salt, acid, solute, inorganic compound, organic compound, density, physical property, chemical property