Science - 2018-19

6.4 - Atoms, Elements, & Compounds

The student will investigate and understand that all matter is made up of atoms. Key concepts include
a) atoms consist of particles, including electrons, protons, and neutrons;
b) atoms of a particular element are alike but are different from atoms of other elements;
c) elements may be represented by chemical symbols;
d) two or more atoms interact to form new substances, which are held together by electrical forces (bonds);
e) compounds may be represented by chemical formulas;
f) chemical equations can be used to model chemical changes; and
g) a limited number of elements comprise the largest portion of the solid Earth, living matter, the oceans, and the atmosphere.

Bloom's Levels:  Analyze; Understand

Adopted: 2010


  • Atoms are the building blocks of matter.
  • Atoms can combine in a variety of ratios to create compounds, represented by chemical formulas.
  • Matter can undergo a variety of changes.
  • Changes in matter are accompanied by changes in energy and are represented by chemical equations.

  • I can identify elements from a model.
  • I can identify elements in a compound based on their symbols.
  • I can model chemical reactions, such as the combustion of diesel in the school bus engine.
  • I can describe the compounds in my food and drinks.
  • I can identify and model chemical changes in my daily life, such as cooking food, combustion engines, and medications.
  • I can identify the origin of a soil sample based on its composition.


  • The basic structural components of a typical atom are electrons, protons, and neutrons. Protons and neutrons comprise the nucleus of an atom.
  • An element is a form of matter made up of one type of atom. The atoms of an element are basically alike, though the number of neutrons may vary.
  • The atoms of one element differ from those of another element in the number of protons.
  • Elements can be represented by chemical symbols.
  • Two or more atoms of different elements may combine to form a compound.
  • Compounds can be represented by chemical formulas. Each different element in the compound is represented by its unique symbol. The number of each type of element in the compound (other than 1) is reprsented by a small number (the subscript) to the right of the element symbol.
  • Chemical equations can be used to model chemical changes, illustrating how elements become rearranged in a chemical reaction.
  • A limited number of elements, including silicon, aluminum, iron, sodium, calcium, potassium, magnesium, hydrogen, oxygen, nitrogen, and carbon, form the largest portion of Earth's crust, living matter, the oceans, and the atmosphere.


In order to meet this standard, it is expected that students will

a)  create and interpret a simplified modern model of the structure of an atom.

b)  compare and contrast the atomic structure of two different elements.

c)  explain that elements are represented by symbols.

e)  identify the name and number of each element present in a simple molecule or compound, such as O2, H2O, CO2, or CaCO3.

f)  model a simple chemical change with an equation and account for all atoms. Distinguish the types of elements and number of each element in the chemical equation. (Balancing equations will be further developed in Physical Science.)

g)  name some of the predominant elements found in the atmosphere, the oceans, living matter, and Earth’s crust.


atom, proton, neutron, electron, nucleus, atomic number, element, compound, matter, chemical equation, chemical change, physical change

Updated: Jun 29, 2018