Rules for Significant Figures (sig figs, s.f.)
A. Read from the left and start counting sig figs when you encounter the first non-zero digit
1. All non zero numbers are significant (meaning they count as sig figs)
613 has three sig figs
123456 has six sig
How Do We Name Chemical Compounds?
Compound formula represents
two different atoms!
1. For metals that have a single charge:
Metal< >nonmetals stem+ide
NaCl sodium chloride
Formula Writing and Naming Tips
1. Ionic Compounds:
a. given a name, you should be able to write the chemical formula for an ionic
i. be aware of what each part of the polyatomic ion means, i.e. PO43means a charge of 3- for the WHOLE PO4 structur
Polyatomic Oxyanion Naming
Polyatomic oxyanions come in groups of (at most) four:
The blank is the common root for the name. For example sulf would go in the blank for:
The formulas for
AP Naming Compounds Review
What does HONClBrIF mean? How do you use it?
How does the name of a single nonmetal atom change when it forms an ion?
How do you find the charge of the positive and negative ions for atoms on the periodic tab
Basic Concepts Test Review
1. E s s ay:
For a given scientist, be prepared to discuss what the scientist discovered AND how the results of his
experiment advanced the understanding of atomic structure? Ex: B/c over 99% of alpha particles went
Determining Molecular Formulas
1) Determine the empirical formula for the given data, OR use the given empirical formula
2) Calculate the molar mass of the empirical formula from step 1)
3) Use the formula:
the supplied molar mass of the (actual or true)
Determining Empirical Formulas From Experiment
In an actual experiment, a precisely measured mass of a compound undergoes a reaction, and the
products are carefully collected and massed. The products will contain the elements that were in the
Empirical and Molecular Formula Worksheet
SHOW WORK ON A SEPARATE SHEET OF PAPER.
Write the empirical formula for the following compounds.
A compound with an empirical formula of C2OH4 and a molar mass of 88
Empirical and Molecular Formulas from Experiment
1) An organic compound contains only carbon, hydrogen, and chlorine. Combustion of a 1.50 g
sample produces 3.52 g of CO2. In a separate reaction, a 1.00 g sample reacts with Ag+, producing
1.27 g of AgCl.
Sometimes it is necessary to perform two experiments to obtain all the necessary information about the
elements in an unknown compound. Note: Most often, the sample masses are different in each
Ex: In the problem below, two exper
Solution Chemistry Test
1. Solution Stoichiometry
a. Write a completed, balanced, net ionic chemical equation (watch the charges when you
write your formulas!)
b. Determine if there was a reaction or not. If there was
c. Remember to use the mo