Atomic Structure and Radioactivity

Beanium lab

September 22, 2015
Today we conducted an experiment to identify the average atomic mass of a newly discovered element, beanium. To identify the atomic mass, the first step was to count up all the beans in the sample as well as how many there were in each type of bean. This information allowed us to calculate the average atomic mass by multiplying each isotope by its mass abundance and adding them together. [(mass)(% abundance)]+[(mass)(%abundance)]= average atomic mass

Radioactive Decay

Today in class, the lecture was over some of the different types of radioactive decay. These decays included alpha particle decay, beta particle decay, and gamma decay. Although I have seen and heard about alpha, beta, and gamma, I did not know what they pertained to, or what they did. I now know that they are radioactive reactions going on inside elements that can change the mass or atomic number of an element, or in the case of a gamma decay, just release photons without changing the mass or atomic number. During an alpha decay, an element's mass lowers by four, and it's number of protons decreases by two. In the case of a beta particle decay, an element does not experience any change in it's mass, however, it does experience an increase of one proton. The forms in which these decays take are helium nucleus for an alpha decay, an electron for a beta decay, and energy for a gamma decay. These types of radioactive decay are a common occurrence in elements.

Atomic Theories

On Wednesday, we started taking notes for our unit over atomic structure and radioactivity. The notes were over atomic theories, specifically those created by Dalton, Rutherford, and Thompson. Dalton's theory includes the following statements: all elements are composed of atoms; all atoms of a given element are identical; atoms of different elements are different; compounds consist of the atoms of different elements; and atoms are indivisible and can't be created or destroyed in a chemical reaction. Rutherford's theory consisted of of atoms containing a small, dense region, or the nucleus, which contained molecules of a positive charge, also known as protons.  Thompson's theory entailed that atoms contained negatively charged molecules, or electrons.

Unit 2 Pretest

On Tuesday we took our Pretest for our second unit in pre-AP chemistry, atomic structure and radioactivity. Based on the Pretest, I think this unit is going to be harder than the last. With the last Pretest I recognized some of the material; whereas, I didn't recognize almost any material for this unit.

Naming Acids

I use this flowchart to help me correctly name acids. The flowchart has helped me memorize the different prefixes and suffixes used to name acids. Factors that determine how an acid is named are whether it contains oxygen, and if so, what the ending of the anion is. If the anion doesn't contain oxygen, it is named using the prefix hydro- and the suffix -ic. Depending on the ending of an anion that does contain oxygen, the suffix is different. For an anion that has the ending -ite, the acid is named with the suffix -ous. For an anion that has the ending -ate, it is named with the suffix -ic

Naming Binary Compounds

This flowchart helps me to differentiate how each binary compound is named. By using the flowchart, I am able to determine which type of binary compound it is, as well as, how the compound would be named. If a binary compound doesn't contain a metal, it is a Type III binary compound and is named using prefixes. When there is a metal present in the binary compound, it is either a Type I or Type II binary compound. In order to differentiate between Type I and Type II, one must look at whether the metal forms more than one cation. If the metal doesn't form more than one cation, it's a Type I binary compound and is named using the element name for the cation. When a metal does form more than one cation, it's a Type II binary compound and is named by determining the charge of the cation and using a Roman numeral after the element name for the cation.