Science - 2018-19

CH.3 b-c, e - Chemical Formulas, Equations, & Reactions

The student will investigate and understand how conservation of energy and matter is expressed in chemical formulas and balanced equations. Key concepts include:
b) balancing chemical equations;
c) writing chemical formulas;
e) reaction types.

Bloom's Levels:  Analyze; Understand

Adopted: 2010


  • Matter can be neither created nor destroyed.
  • Chemical bonding occurs as a result of attractive forces between particles.

  • I can determine how many cookies I can make from a set of ingredients.
  • I can determine what substances are in my food.
  • I can create new compounds.


  • When pairs of elements form two or more compounds, the masses of one element that combine with a fixed mass of the other element form simple, whole-number ratios (Law of Multiple Proportions).
  • Compounds have different properties than the elements from which they are compounds.
  • Conservation of matter is represented in balanced chemical equations. A coefficient is a quantity that precedes a reactant or product formula in a chemical equation and indicates the relative number of particles involved in the reaction.


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

b) transform word equations into chemical equations and balance chemical equations.

c) predict, draw, and name molecular shapes (bent, linear, trigonal planar, tetrahedral, and trigonal pyramidal).

     write the chemical formulas for certain common substances, such as ammonia, water, carbon monoxide, carbon dioxide, sulfur dioxide, and carbon tetrafluoride.

     use polyatomic ions for naming and writing formulas of ionic compounds, including carbonate, sulfate, nitrate, hydroxide, phosphate, and ammonium.

     use valence shell electron pair repulsion (VSEPR) model to draw and name molecular shapes (bent, linear, trigonal planar, tetrahedral, and trigonal pyramidal).

     recognize polar molecules and non-polar molecules.

e) classify types of chemical reactions as synthesis, decomposition, single replacement, double replacement, neutralization, and/or combustion.


aqueous solution, chemical equation, chemical reaction, coefficient, combustion reaction, complete ionic equation, decomposition reaction, double replacement reaction, net ionic equation, precipitate, product, reactant, single-replacement reaction, solute, solvent, spectator ion, synthesis reaction

Updated: Nov 19, 2017