The Atom Chemistry Vocabulary and notes

Vocabulary - 1 Element - substance that cannot be broken down into other substances by chemical/physical means Atomic number- number of protons in nucleus Atomic mass unit (amu) -unit used to measure particles in atoms Valence electron -electrons located fartherest away from nucleus Chemical bond- force that holds chemicals together

ATOM

Atom notes Nucleus-core of atom, made of proton (+), neutrons Atom neutral when protons = electrons (-) Atomic number =‘s number of protons AMU measures particles in atom Electrons roam around nucleus in electronic cloud – are in constant motion Protons have almost 2000 times as much mass as electrons

Atom notes cont. Electrons attract protons in nearby atoms Attraction forms molecules Mass =‘s protons + neutrons 1 st shell = 2 2 nd shell =8 3 rd shell = 18 4 th shell =32 5 th,6 th,7 th have various amts., depending on type of molecule formed with max of 32, 18, and 2 respectively Most of the atoms volume is the space where the electrons move

Valence Electrons Are the electrons that are fartherest away from the nucleus Determines many properties of the atom and therefore of the element Forms chemical bonds with other atoms Can range from 1 to 8 Are represented by an electron dot diagram

Modeling Atoms – Lab ___ Question – What can we learn about atoms by studying different models of them? Hypothesis- Materials - different colored dots (3 colors) 3 pipe cleaners different colored beads (3 colors) periodic table different colored beads (3 colors) periodic table clear plastic wrap clear plastic ball clear plastic wrap clear plastic ball clay clay Procedure – 1. You will need to refer to your periodic table to complete this lab. 2 Find the element carbon on the periodic table. Using your colored dots create a model of a carbon atom in data table 1. Be sure to include a legend telling which color represents the protons, electron, and neutrons.

Modeling Atoms cont. 3. Now find the element nitrogen on the periodic table. Using the pipe cleaners and beads construct a 3-D model of a nitrogen atom. Glue this model in to data table 2, remembering to provide a legend for the bead color. 4. Next you will be constructing a model of the element boron using the clay and the clear plastic ball. Decide which colors of clay will represent the parts of the nucleus and which will represent the electrons. 5. Wrap the nucleus in the clear plastic wrap and suspend it between the 2 hemispheres of the plastic ball. This allow the nucleus to hang suspended down the center when the ball is put back together. Now place the clay electrons on the outside surface of the plastic sphere.

Data Table 1 Data Table 2

Modeling Atoms cont. Results – Conclusion – 1. How was the first model different from the second model? How was it the same? 2. How was the third model different from the first two? In what way was it the same? 3. What are the strengths and weaknesses of each model? 4. How was the periodic table helpful in making the models? 5. Why is it helpful for a scientist to build models such as these? 6. What do these models show? What do they not show? 7. What will happen to our models if we learn something new about atoms?

Extensions Activities and Labs

Crossword puzzle w/ vocabulary Seek and find puzzle w/ vocabulary Lab - Atomic Models Lab – Pepper Picker Upper